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Anthony H C Huang - One of the best experts on this subject based on the ideXlab platform.
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Bioinformatics Reveal Five Lineages of Oleosins and the Mechanism of Lineage Evolution Related to Structure/Function from Green Algae to Seed Plants
Plant physiology, 2015Co-Authors: Ming-der Huang, Anthony H C HuangAbstract:Plant cells contain subcellular lipid droplets with a triacylglycerol matrix enclosed by a layer of phospholipids and the small structural protein Oleosin. Oleosins possess a conserved central hydrophobic hairpin of approximately 72 residues penetrating into the lipid droplet matrix and amphipathic amino- and carboxyl (C)-terminal peptides lying on the phospholipid surface. Bioinformatics of 1,000 Oleosins of green algae and all plants emphasizing biological implications reveal five Oleosin lineages: primitive (in green algae, mosses, and ferns), universal (U; all land plants), and three in specific organs or phylogenetic groups, termed seed low-molecular-weight (SL; seed plants), seed high-molecular-weight (SH; angiosperms), and tapetum (T; Brassicaceae) Oleosins. Transition from one lineage to the next is depicted from lineage intermediates at junctions of phylogeny and organ distributions. Within a species, each lineage, except the T Oleosin lineage, has one to four genes per haploid genome, only approximately two of which are active. Primitive Oleosins already possess all the general characteristics of Oleosins. U Oleosins have C-terminal sequences as highly conserved as the hairpin sequences; thus, U Oleosins including their C-terminal peptide exert indispensable, unknown functions. SL and SH Oleosin transcripts in seeds are in an approximately 1:1 ratio, which suggests the occurrence of SL-SH Oleosin dimers/multimers. T Oleosins in Brassicaceae are encoded by rapidly evolved multitandem genes for alkane storage and transfer. Overall, Oleosins have evolved to retain conserved hairpin structures but diversified for unique structures and functions in specific cells and plant families. Also, our studies reveal Oleosin in avocado (Persea americana) mesocarp and no acyltransferase/lipase motifs in most Oleosins.
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Tandem Oleosin genes in a cluster acquired in Brassicaceae created tapetosomes and conferred additive benefit of pollen vigor
Proceedings of the National Academy of Sciences of the United States of America, 2013Co-Authors: Chien-yu Huang, Ming-der Huang, Pei-ying Chen, Chih-hua Tsou, Wann-neng Jane, Anthony H C HuangAbstract:During evolution, genomes expanded via whole-genome, segmental, tandem, and individual-gene duplications, and the emerged redundant paralogs would be eliminated or retained owing to selective neutrality or adaptive benefit and further functional divergence. Here we show that tandem paralogs can contribute adaptive quantitative benefit and thus have been retained in a lineage-specific manner. In Brassicaceae, a tandem Oleosin gene cluster of five to nine paralogs encodes ample tapetum-specific Oleosins located in abundant organelles called tapetosomes in flower anthers. Tapetosomes coordinate the storage of lipids and flavonoids and their transport to the adjacent maturing pollen as the coat to serve various functions. Transfer-DNA and siRNA mutants of Arabidopsis thaliana with knockout and knockdown of different tandem Oleosin paralogs had quantitative and correlated loss of organized structures of the tapetosomes, pollen-coat materials, and pollen tolerance to dehydration. Complementation with the knockout paralog restored the losses. Cleomaceae is the family closest to Brassicaceae. Cleome species did not contain the tandem Oleosin gene cluster, tapetum Oleosin transcripts, tapetosomes, or pollen tolerant to dehydration. Cleome hassleriana transformed with an Arabidopsis Oleosin gene for tapetum expression possessed primitive tapetosomes and pollen tolerant to dehydration. We propose that during early evolution of Brassicaceae, a duplicate Oleosin gene mutated from expression in seed to the tapetum. The tapetum Oleosin generated primitive tapetosomes that organized stored lipids and flavonoids for their effective transfer to the pollen surface for greater pollen vitality. The resulting adaptive benefit led to retention of tandem-duplicated Oleosin genes for production of more Oleosin and modern tapetosomes.
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Oleosin of subcellular lipid droplets evolved in green algae
Plant physiology, 2013Co-Authors: Nan-lan Huang, Ming-der Huang, Tung-ling L. Chen, Anthony H C HuangAbstract:In primitive and higher plants, intracellular storage lipid droplets (LDs) of triacylglycerols are stabilized with a surface layer of phospholipids and Oleosin. In chlorophytes (green algae), a protein termed major lipid-droplet protein (MLDP) rather than Oleosin on LDs was recently reported. We explored whether MLDP was present directly on algal LDs and whether algae had Oleosin genes and Oleosins. Immunofluorescence microscopy revealed that MLDP in the chlorophyte Chlamydomonas reinhardtii was associated with endoplasmic reticulum subdomains adjacent to but not directly on LDs. In C. reinhardtii, low levels of a transcript encoding an Oleosin-like protein (oleolike) in zygotes-tetrads and a transcript encoding Oleosin in vegetative cells transferred to an acetate-enriched medium were found in transcriptomes and by reverse transcription-polymerase chain reaction. The C. reinhardtii LD fraction contained minimal proteins with no detectable oleolike or Oleosin. Several charophytes (advanced green algae) possessed low levels of transcripts encoding Oleosin but not oleolike. In the charophyte Spirogyra grevilleana, levels of Oleosin transcripts increased greatly in cells undergoing conjugation for zygote formation, and the LD fraction from these cells contained minimal proteins, two of which were Oleosins identified via proteomics. Because the minimal oleolike and Oleosins in algae were difficult to detect, we tested their subcellular locations in Physcomitrella patens transformed with the respective algal genes tagged with a Green Fluorescent Protein gene and localized the algal proteins on P. patens LDs. Overall, Oleosin genes having weak and cell/development-specific expression were present in green algae. We present a hypothesis for the evolution of Oleosins from algae to plants.
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Oil Bodies and Oleosins in Physcomitrella Possess Characteristics Representative of Early Trends in Evolution
Plant physiology, 2009Co-Authors: Chien-yu Huang, Chun-i Chung, Yao-cheng Lin, Yue-ie C. Hsing, Anthony H C HuangAbstract:Searches of sequenced genomes of diverse organisms revealed that the moss Physcomitrella patens is the most primitive organism possessing Oleosin genes. Microscopy examination of Physcomitrella revealed that oil bodies (OBs) were abundant in the photosynthetic vegetative gametophyte and the reproductive spore. Chromatography illustrated the neutral lipids in OBs isolated from the gametophyte to be largely steryl esters and triacylglycerols, and SDS-PAGE showed the major proteins to be Oleosins. Reverse transcription-PCR revealed the expression of all three Oleosin genes to be tissue specific. This tissue specificity was greatly altered via alternative splicing, a control mechanism of Oleosin gene expression unknown in higher plants. During the production of sex organs at the tips of gametophyte branches, the number of OBs in the top gametophyte tissue decreased concomitant with increases in the number of peroxisomes and level of transcripts encoding the glyoxylate cycle enzymes; thus, the OBs are food reserves for gluconeogenesis. In spores during germination, peroxisomes adjacent to OBs, along with transcripts encoding the glyoxylate cycle enzymes, appeared; thus, the spore OBs are food reserves for gluconeogenesis and equivalent to seed OBs. The one-cell-layer gametophyte could be observed easily with confocal microscopy for the subcellular OBs and other structures. Transient expression of various gene constructs transformed into gametophyte cells revealed that all OBs were linked to the endoplasmic reticulum (ER), that Oleosins were synthesized in extended regions of the ER, and that two different Oleosins were colocated in all OBs.
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Oil Bodies and Oleosins in Physcomitrella Possess Characteristics Representative of Early Trends
2009Co-Authors: Chien-yu Huang, Chun-i Chung, Yao-cheng Lin, Yue-ie C. Hsing, Anthony H C HuangAbstract:Searches of sequenced genomes of diverse organisms revealed that the moss Physcomitrella patens is the most primitive organism possessing Oleosin genes. Microscopy examination of Physcomitrella revealed that oil bodies (OBs) were abundant in the photosynthetic vegetative gametophyte and the reproductive spore. Chromatography illustrated the neutral lipids in OBs isolated from the gametophyte to be largely steryl esters and triacylglycerols, and SDS-PAGE showed the major proteins to be Oleosins. Reverse transcription-PCR revealed the expression of all three Oleosin genes to be tissue specific. This tissue specificity was greatly altered via alternative splicing, a control mechanism of Oleosin gene expression unknown in higher plants. During the production of sex organs at the tips of gametophyte branches, the number of OBs in the top gametophyte tissue decreased concomitant with increases in the number of peroxisomes and level of transcripts encoding the glyoxylate cycle enzymes; thus, the OBs are food reserves for gluconeogenesis. In spores during germination, peroxisomes adjacent to OBs, along with transcripts encoding the glyoxylate cycle enzymes, appeared; thus, the spore OBs are food reserves for gluconeogenesis and equivalent to seed OBs. The one-cell-layer gametophyte could be observed easily with confocal microscopy for the subcellular OBs and other structures. Transient expression of various gene constructs transformed into gametophyte cells revealed that all OBs were linked to the endoplasmic reticulum (ER), that Oleosins were synthesized in extended regions of the ER, and that two different Oleosins were colocated in all OBs.
Yeming Chen - One of the best experts on this subject based on the ideXlab platform.
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Soybean P34 Probable Thiol Protease Probably Has Proteolytic Activity on Oleosins.
Journal of agricultural and food chemistry, 2017Co-Authors: Luping Zhao, Xiangzhen Kong, Yufei Hua, Caimeng Zhang, Yeming ChenAbstract:P34 probable thiol protease (P34) and Gly m Bd 30K (30K) show high relationship with the protease of 24 kDa Oleosin of soybean oil bodies. In this study, 9 day germinated soybean was used to separate bioprocessed P34 (P32) from bioprocessed 30K (28K). Interestingly, P32 existed as dimer, whereas 28K existed as monomer; a P32-rich sample had proteolytic activity and high cleavage site specificity (Lys-Thr of 24 kDa Oleosin), whereas a 28K-rich sample showed low proteolytic activity; the P32-rich sample contained one thiol protease. After mixing with purified oil bodies, all P32 dimers were dissociated and bound to 24 kDa Oleosins to form P32–24 kDa Oleosin complexes. By incubation, 24 kDa Oleosin was preferentially hydrolyzed, and two hydrolyzed products (HPs; 17 and 7 kDa) were confirmed. After most of 24 kDa Oleosin was hydrolyzed, some P32 existed as dimer, and the other as P32–17 kDa HP. It was suggested that P32 was the protease.
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Soybean P34 Probable Thiol Protease Probably Has Proteolytic Activity on Oleosins
2017Co-Authors: Luping Zhao, Xiangzhen Kong, Yufei Hua, Caimeng Zhang, Yeming ChenAbstract:P34 probable thiol protease (P34) and Gly m Bd 30K (30K) show high relationship with the protease of 24 kDa Oleosin of soybean oil bodies. In this study, 9 day germinated soybean was used to separate bioprocessed P34 (P32) from bioprocessed 30K (28K). Interestingly, P32 existed as dimer, whereas 28K existed as monomer; a P32-rich sample had proteolytic activity and high cleavage site specificity (Lys-Thr of 24 kDa Oleosin), whereas a 28K-rich sample showed low proteolytic activity; the P32-rich sample contained one thiol protease. After mixing with purified oil bodies, all P32 dimers were dissociated and bound to 24 kDa Oleosins to form P32–24 kDa Oleosin complexes. By incubation, 24 kDa Oleosin was preferentially hydrolyzed, and two hydrolyzed products (HPs; 17 and 7 kDa) were confirmed. After most of 24 kDa Oleosin was hydrolyzed, some P32 existed as dimer, and the other as P32–17 kDa HP. It was suggested that P32 was the protease
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effects of ph on protein components of extracted oil bodies from diverse plant seeds and endogenous protease induced Oleosin hydrolysis
Food Chemistry, 2016Co-Authors: Luping Zhao, Xiangzhen Kong, Yeming Chen, Yajing Chen, Yufei HuaAbstract:Plant seeds are used to extract oil bodies for diverse applications, but oil bodies extracted at different pH values exhibit different properties. Jicama, sunflower, peanut, castor bean, rapeseed, and sesame were selected to examine the effects of pH (6.5-11.0) on the protein components of oil bodies and the Oleosin hydrolysis in pH 6.5-extracted oil bodies. In addition to Oleosins, many extrinsic proteins (globulins, 2S albumin, and enzymes) were present in pH 6.5-extracted oil bodies. Globulins were mostly removed at pH 8.0, whereas 2S albumins were removed at pH 11.0. At pH 11.0, highly purified oil bodies were obtained from jicama, sunflower, peanut, and sesame, whereas lipase remained in the castor bean oil bodies and many enzymes in the rapeseed oil bodies. Endogenous protease-induced hydrolysis of Oleosins occurred in all selected plant seeds. Oleosins with larger sizes were hydrolysed more quickly than Oleosins with smaller sizes in each plant seed.
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The characterization of soybean oil body integral Oleosin isoforms and the effects of alkaline pH on them.
Food chemistry, 2015Co-Authors: Yanyun Cao, Luping Zhao, Ying Yusang, Xiangzhen Kong, Yufei Hua, Yeming ChenAbstract:Oil body, an organelle in seed cell (naturally pre-emulsified oil), has great potentials to be used in food, cosmetics, pharmaceutical and other applications requiring stable oil-in-water emulsions. Researchers have tried to extract oil body by alkaline buffers, which are beneficial for removing contaminated proteins. But it is not clear whether alkaline buffers could remove oil body integral proteins (mainly Oleosins), which could keep oil body integrity and stability. In this study, seven Oleosin isoforms were identified for soybean oil body (three isoforms, 24 kDa; three isoforms, 18 kDa; one isoform, 16kDa). Oleosins were not glycoproteins and 24 kDa Oleosin isoforms possessed less thiol groups than 18 kDa ones. It was found that alkaline pH not only removed contaminated proteins but also Oleosins, and more and more Oleosins were removed with increasing alkaline pH.
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Oleosins (24 and 18 kDa) Are Hydrolyzed Not Only in Extracted Soybean Oil Bodies but Also in Soybean Germination
Journal of agricultural and food chemistry, 2014Co-Authors: Yeming Chen, Yanyun Cao, Luping Zhao, Xiangzhen Kong, Yufei HuaAbstract:After oil bodies (OBs) were extracted from ungerminated soybean by pH 6.8 extraction, it was found that 24 and 18 kDa Oleosins were hydrolyzed in the extracted OBs, which contained many OB extrinsic proteins (i.e., lipoxygenase, β-conglycinin, γ-conglycinin, β-amylase, glycinin, Gly m Bd 30K (Bd 30K), and P34 probable thiol protease (P34)) as well as OB intrinsic proteins. In this study, some properties (specificity, optimal pH and temperature) of the proteases of 24 and 18 kDa Oleosins and the Oleosin hydrolysis in soybean germination were examined, and the high relationship between Bd 30K/P34 and the proteases was also discussed. The results showed (1) the proteases were OB extrinsic proteins, which had high specificity to hydrolyze 24 and 18 kDa Oleosins, and cleaved the specific peptide bonds to form limited hydrolyzed products; (2) 24 and 18 kDa Oleosins were not hydrolyzed in the absence of Bd 30K and P34 (or some Tricine-SDS-PAGE undetectable proteins); (3) the protease of 24 kDa Oleosin had strong...
Jason T.c. Tzen - One of the best experts on this subject based on the ideXlab platform.
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Recent Biotechnological Applications Using Oleosins
The Open Biotechnology Journal, 2008Co-Authors: N.j. Roberts, R.w. Scott, Jason T.c. TzenAbstract:Oleosins are naturally occurring, small (15-24 kDa), amphipathic, plant proteins that prevent the coalescence of oil bodies (OBs) during seed and pollen maturation. The physiochemical properties of Oleosins and their association with OBs have led to a broad array of potential applications in biotechnology utilizing native or recombinant forms of Oleosin or Oleosin-fused polypeptides. This review begins by briefly outlining the current understanding of Oleosin topology, oil body assembly and potential health issues. A schematic model is given to potentially explain the apparent simultaneous existence of parallel and anti-parallel sheets and a figure summarizing the process of Oleosin translation through to oil body formation in vivo is also presented. The applications for Oleosins, the associated modes of action and their relevant patents are then discussed in six areas: recombinant protein purification; generating protein complexes; in planta delivery; emulsification; artificial oil bodies; and modifications to the properties of Oleosin itself by creating polyOleosin. Flowering plants store triacylglycerol (TAG) in their seeds as an energy source for germination. The TAG is con- tained within discreet structures called oil bodies (OBs), which are 0.5-2μm in diameter and consist of a TAG core surrounded by a phospholipid monolayer embedded with proteinaceous emulsifiers - predominantly Oleosins (1). OBs consist of 0.5-3.5% protein; of this 80-90% is Oleosin with the majority of the remainder consisting of the proteins caleosin (calcium binding) and sterOleosin (sterol binding) (2). The role of the Oleosins is to stop the OBs coalescing as the cells dehydrate; thus maintaining the appropriate surface area/volume ratio of each OB and ensuring the rapid avail- ability of TAG during germination. Oleosins have also been reported in pollen (3-5) and the female gametophyte of gym- nosperms (6). The unique properties of Oleosins form the basis of a number of applications including: purifying proteins; forma- tion of multimeric protein complexes; emulsification; deliv- ery of bioactives; generation of multivalent bioactives and even as a potential flavour enhancer. In order to more fully understand the principals of these applications it is necessary to understand the properties of Oleosins; it is the purpose of this review to discuss their properties and applications. 1.1. Oleosin Topology
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Minimizing the central hydrophobic domain in Oleosin for the constitution of artificial oil bodies.
Journal of agricultural and food chemistry, 2007Co-Authors: Chi-chung Peng, Viola S. Y. Lee, Meei-yn Lin, Hsin-yi Huang, Jason T.c. TzenAbstract:Oleosin, a unique structural protein anchoring onto the surface of seed oil bodies by its central hydrophobic domain, stabilizes these lipid-storage organelles as discrete entities. Stable artificial oil bodies have been successfully constituted with native or recombinant Oleosins. In this study, recombinant sesame Oleosin with 12 residues stepwise truncated from its central hydrophobic domain of 72 residues was overexpressed in Escherichia coli, was purified to homogeneity, and was used for the constitution. Artificial oil bodies constituted by truncated Oleosins with the central hydrophobic domain longer than 36 residues were as stable as native sesame oil bodies, and those constituted by truncated Oleosins lacking more than half of the original central hydrophobic domain inclined to coalesce upon collision or aggregation.
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Stable oil bodies sheltered by a unique Oleosin in lily pollen.
Plant & cell physiology, 2007Co-Authors: Pei-luen Jiang, Co-shing Wang, Chia-mei Hsu, Guang-yuh Jauh, Jason T.c. TzenAbstract:Stable oil bodies were purified from mature lily (Lilium longiflorum Thunb.) pollen. The integrity of pollen oil bodies was maintained via electronegative repulsion and steric hindrance possibly provided by their surface proteins. Immunodetection revealed that a major protein of 18 kDa was exclusively present in pollen oil bodies and massively accumulated in late stages of pollen maturation. According to mass spectrometric analyses, this oil body protein possessed a tryptic fragment of 13 residues matching that of a theoretical rice Oleosin. A complete cDNA fragment encoding this putative Oleosin was obtained by PCR cloning with primers derived from its known 13-residue sequence. Sequence analysis as well as immunological non-cross-reactivity suggests that this pollen Oleosin represents a distinct class in comparison with Oleosins found in seed oil bodies and tapetum. In pollen cells observed by electron microscopy, oil bodies were presumably surrounded by tubular membrane structures, and encapsulated in the vacuoles after germination. It seems that pollen oil bodies are mobilized via a different route from that of glyoxysomal mobilization of seed oil bodies after germination.
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Gene family of Oleosin isoforms and their structural stabilization in sesame seed oil bodies.
Bioscience biotechnology and biochemistry, 2002Co-Authors: Sorgan S. K. Tai, Miles C. M. Chen, Chi-chung Peng, Jason T.c. TzenAbstract:Oleosins are structural proteins sheltering the oil bodies of plant seeds. Two isoform classes termed H- and L-Oleosin are present in diverse angiosperms. Two H-Oleosins and one L-Oleosin were identified in sesame oil bodies from the protein sequences deduced from their corresponding cDNA clones. Sequence analysis showed that the main difference between the H- and L-isoforms is an insertion of 18 residues in the C-terminal domain of H-Oleosins. H-Oleosin, presumably derived from L-Oleosin, was duplicated independently in several species. All known Oleosins can be classified as one of these two isoforms. Single copy or a low copy number was detected by Southern hybridization for each of the three Oleosin genes in the sesame genome. Northern hybridization showed that the three Oleosin genes were transcribed in maturing seeds where oil bodies are being assembled. Artificial oil bodies were reconstituted with triacylglycerol, phospholipid, and sesame Oleosin isoforms. The results indicated that reconstituted oil bodies could be stabilized by both isoforms, but L-Oleosin gave slightly more structural stability than H-Oleosin.
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Genomic cloning of 18 kDa Oleosin and detection of triacylglycerols and Oleosin isoforms in maturing rice and postgerminative seedlings.
Journal of biochemistry, 1998Co-Authors: Lian-du Wang, Peng-wen Chen, Liang-jwu Chen, Jason T.c. TzenAbstract:Oleosins are hydrophobic proteins localized abundantly in the oil bodies of plant seeds. Two distinct Oleosin isoforms of molecular masses 18 and 16 kDa are present in rice oil bodies. These isoforms were found in similar ratio in rice embryos and aleurone layers. To survey potential DNA sequences involved in the activation of Oleosin genes, a genomic clone of rice 18 kDa Oleosin was sequenced, and its 5'-flanking region was compared with that of the known rice 16 kDa Oleosin gene. Corresponding mRNAs of the two rice Oleosin isoforms appeared seven days after pollination and vanished in mature seeds. Triacylglycerols and Oleosins were accumulated concomitantly in maturing rice reeds in accord with the active assembly of oil bodies, and partly mobilized in postgerminative seedlings. Approximately 60% of the stored triacylglycerols in rice were not utilized: while the majority of oil bodies in embryos were mobilized in five days after imbibition, those in aleurone layers remained intact in postgerminative seedlings.
Yufei Hua - One of the best experts on this subject based on the ideXlab platform.
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Soybean P34 Probable Thiol Protease Probably Has Proteolytic Activity on Oleosins.
Journal of agricultural and food chemistry, 2017Co-Authors: Luping Zhao, Xiangzhen Kong, Yufei Hua, Caimeng Zhang, Yeming ChenAbstract:P34 probable thiol protease (P34) and Gly m Bd 30K (30K) show high relationship with the protease of 24 kDa Oleosin of soybean oil bodies. In this study, 9 day germinated soybean was used to separate bioprocessed P34 (P32) from bioprocessed 30K (28K). Interestingly, P32 existed as dimer, whereas 28K existed as monomer; a P32-rich sample had proteolytic activity and high cleavage site specificity (Lys-Thr of 24 kDa Oleosin), whereas a 28K-rich sample showed low proteolytic activity; the P32-rich sample contained one thiol protease. After mixing with purified oil bodies, all P32 dimers were dissociated and bound to 24 kDa Oleosins to form P32–24 kDa Oleosin complexes. By incubation, 24 kDa Oleosin was preferentially hydrolyzed, and two hydrolyzed products (HPs; 17 and 7 kDa) were confirmed. After most of 24 kDa Oleosin was hydrolyzed, some P32 existed as dimer, and the other as P32–17 kDa HP. It was suggested that P32 was the protease.
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Soybean P34 Probable Thiol Protease Probably Has Proteolytic Activity on Oleosins
2017Co-Authors: Luping Zhao, Xiangzhen Kong, Yufei Hua, Caimeng Zhang, Yeming ChenAbstract:P34 probable thiol protease (P34) and Gly m Bd 30K (30K) show high relationship with the protease of 24 kDa Oleosin of soybean oil bodies. In this study, 9 day germinated soybean was used to separate bioprocessed P34 (P32) from bioprocessed 30K (28K). Interestingly, P32 existed as dimer, whereas 28K existed as monomer; a P32-rich sample had proteolytic activity and high cleavage site specificity (Lys-Thr of 24 kDa Oleosin), whereas a 28K-rich sample showed low proteolytic activity; the P32-rich sample contained one thiol protease. After mixing with purified oil bodies, all P32 dimers were dissociated and bound to 24 kDa Oleosins to form P32–24 kDa Oleosin complexes. By incubation, 24 kDa Oleosin was preferentially hydrolyzed, and two hydrolyzed products (HPs; 17 and 7 kDa) were confirmed. After most of 24 kDa Oleosin was hydrolyzed, some P32 existed as dimer, and the other as P32–17 kDa HP. It was suggested that P32 was the protease
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effects of ph on protein components of extracted oil bodies from diverse plant seeds and endogenous protease induced Oleosin hydrolysis
Food Chemistry, 2016Co-Authors: Luping Zhao, Xiangzhen Kong, Yeming Chen, Yajing Chen, Yufei HuaAbstract:Plant seeds are used to extract oil bodies for diverse applications, but oil bodies extracted at different pH values exhibit different properties. Jicama, sunflower, peanut, castor bean, rapeseed, and sesame were selected to examine the effects of pH (6.5-11.0) on the protein components of oil bodies and the Oleosin hydrolysis in pH 6.5-extracted oil bodies. In addition to Oleosins, many extrinsic proteins (globulins, 2S albumin, and enzymes) were present in pH 6.5-extracted oil bodies. Globulins were mostly removed at pH 8.0, whereas 2S albumins were removed at pH 11.0. At pH 11.0, highly purified oil bodies were obtained from jicama, sunflower, peanut, and sesame, whereas lipase remained in the castor bean oil bodies and many enzymes in the rapeseed oil bodies. Endogenous protease-induced hydrolysis of Oleosins occurred in all selected plant seeds. Oleosins with larger sizes were hydrolysed more quickly than Oleosins with smaller sizes in each plant seed.
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The characterization of soybean oil body integral Oleosin isoforms and the effects of alkaline pH on them.
Food chemistry, 2015Co-Authors: Yanyun Cao, Luping Zhao, Ying Yusang, Xiangzhen Kong, Yufei Hua, Yeming ChenAbstract:Oil body, an organelle in seed cell (naturally pre-emulsified oil), has great potentials to be used in food, cosmetics, pharmaceutical and other applications requiring stable oil-in-water emulsions. Researchers have tried to extract oil body by alkaline buffers, which are beneficial for removing contaminated proteins. But it is not clear whether alkaline buffers could remove oil body integral proteins (mainly Oleosins), which could keep oil body integrity and stability. In this study, seven Oleosin isoforms were identified for soybean oil body (three isoforms, 24 kDa; three isoforms, 18 kDa; one isoform, 16kDa). Oleosins were not glycoproteins and 24 kDa Oleosin isoforms possessed less thiol groups than 18 kDa ones. It was found that alkaline pH not only removed contaminated proteins but also Oleosins, and more and more Oleosins were removed with increasing alkaline pH.
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Oleosins (24 and 18 kDa) Are Hydrolyzed Not Only in Extracted Soybean Oil Bodies but Also in Soybean Germination
Journal of agricultural and food chemistry, 2014Co-Authors: Yeming Chen, Yanyun Cao, Luping Zhao, Xiangzhen Kong, Yufei HuaAbstract:After oil bodies (OBs) were extracted from ungerminated soybean by pH 6.8 extraction, it was found that 24 and 18 kDa Oleosins were hydrolyzed in the extracted OBs, which contained many OB extrinsic proteins (i.e., lipoxygenase, β-conglycinin, γ-conglycinin, β-amylase, glycinin, Gly m Bd 30K (Bd 30K), and P34 probable thiol protease (P34)) as well as OB intrinsic proteins. In this study, some properties (specificity, optimal pH and temperature) of the proteases of 24 and 18 kDa Oleosins and the Oleosin hydrolysis in soybean germination were examined, and the high relationship between Bd 30K/P34 and the proteases was also discussed. The results showed (1) the proteases were OB extrinsic proteins, which had high specificity to hydrolyze 24 and 18 kDa Oleosins, and cleaved the specific peptide bonds to form limited hydrolyzed products; (2) 24 and 18 kDa Oleosins were not hydrolyzed in the absence of Bd 30K and P34 (or some Tricine-SDS-PAGE undetectable proteins); (3) the protease of 24 kDa Oleosin had strong...
Luping Zhao - One of the best experts on this subject based on the ideXlab platform.
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Soybean P34 Probable Thiol Protease Probably Has Proteolytic Activity on Oleosins.
Journal of agricultural and food chemistry, 2017Co-Authors: Luping Zhao, Xiangzhen Kong, Yufei Hua, Caimeng Zhang, Yeming ChenAbstract:P34 probable thiol protease (P34) and Gly m Bd 30K (30K) show high relationship with the protease of 24 kDa Oleosin of soybean oil bodies. In this study, 9 day germinated soybean was used to separate bioprocessed P34 (P32) from bioprocessed 30K (28K). Interestingly, P32 existed as dimer, whereas 28K existed as monomer; a P32-rich sample had proteolytic activity and high cleavage site specificity (Lys-Thr of 24 kDa Oleosin), whereas a 28K-rich sample showed low proteolytic activity; the P32-rich sample contained one thiol protease. After mixing with purified oil bodies, all P32 dimers were dissociated and bound to 24 kDa Oleosins to form P32–24 kDa Oleosin complexes. By incubation, 24 kDa Oleosin was preferentially hydrolyzed, and two hydrolyzed products (HPs; 17 and 7 kDa) were confirmed. After most of 24 kDa Oleosin was hydrolyzed, some P32 existed as dimer, and the other as P32–17 kDa HP. It was suggested that P32 was the protease.
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Soybean P34 Probable Thiol Protease Probably Has Proteolytic Activity on Oleosins
2017Co-Authors: Luping Zhao, Xiangzhen Kong, Yufei Hua, Caimeng Zhang, Yeming ChenAbstract:P34 probable thiol protease (P34) and Gly m Bd 30K (30K) show high relationship with the protease of 24 kDa Oleosin of soybean oil bodies. In this study, 9 day germinated soybean was used to separate bioprocessed P34 (P32) from bioprocessed 30K (28K). Interestingly, P32 existed as dimer, whereas 28K existed as monomer; a P32-rich sample had proteolytic activity and high cleavage site specificity (Lys-Thr of 24 kDa Oleosin), whereas a 28K-rich sample showed low proteolytic activity; the P32-rich sample contained one thiol protease. After mixing with purified oil bodies, all P32 dimers were dissociated and bound to 24 kDa Oleosins to form P32–24 kDa Oleosin complexes. By incubation, 24 kDa Oleosin was preferentially hydrolyzed, and two hydrolyzed products (HPs; 17 and 7 kDa) were confirmed. After most of 24 kDa Oleosin was hydrolyzed, some P32 existed as dimer, and the other as P32–17 kDa HP. It was suggested that P32 was the protease
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effects of ph on protein components of extracted oil bodies from diverse plant seeds and endogenous protease induced Oleosin hydrolysis
Food Chemistry, 2016Co-Authors: Luping Zhao, Xiangzhen Kong, Yeming Chen, Yajing Chen, Yufei HuaAbstract:Plant seeds are used to extract oil bodies for diverse applications, but oil bodies extracted at different pH values exhibit different properties. Jicama, sunflower, peanut, castor bean, rapeseed, and sesame were selected to examine the effects of pH (6.5-11.0) on the protein components of oil bodies and the Oleosin hydrolysis in pH 6.5-extracted oil bodies. In addition to Oleosins, many extrinsic proteins (globulins, 2S albumin, and enzymes) were present in pH 6.5-extracted oil bodies. Globulins were mostly removed at pH 8.0, whereas 2S albumins were removed at pH 11.0. At pH 11.0, highly purified oil bodies were obtained from jicama, sunflower, peanut, and sesame, whereas lipase remained in the castor bean oil bodies and many enzymes in the rapeseed oil bodies. Endogenous protease-induced hydrolysis of Oleosins occurred in all selected plant seeds. Oleosins with larger sizes were hydrolysed more quickly than Oleosins with smaller sizes in each plant seed.
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The characterization of soybean oil body integral Oleosin isoforms and the effects of alkaline pH on them.
Food chemistry, 2015Co-Authors: Yanyun Cao, Luping Zhao, Ying Yusang, Xiangzhen Kong, Yufei Hua, Yeming ChenAbstract:Oil body, an organelle in seed cell (naturally pre-emulsified oil), has great potentials to be used in food, cosmetics, pharmaceutical and other applications requiring stable oil-in-water emulsions. Researchers have tried to extract oil body by alkaline buffers, which are beneficial for removing contaminated proteins. But it is not clear whether alkaline buffers could remove oil body integral proteins (mainly Oleosins), which could keep oil body integrity and stability. In this study, seven Oleosin isoforms were identified for soybean oil body (three isoforms, 24 kDa; three isoforms, 18 kDa; one isoform, 16kDa). Oleosins were not glycoproteins and 24 kDa Oleosin isoforms possessed less thiol groups than 18 kDa ones. It was found that alkaline pH not only removed contaminated proteins but also Oleosins, and more and more Oleosins were removed with increasing alkaline pH.
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Oleosins (24 and 18 kDa) Are Hydrolyzed Not Only in Extracted Soybean Oil Bodies but Also in Soybean Germination
Journal of agricultural and food chemistry, 2014Co-Authors: Yeming Chen, Yanyun Cao, Luping Zhao, Xiangzhen Kong, Yufei HuaAbstract:After oil bodies (OBs) were extracted from ungerminated soybean by pH 6.8 extraction, it was found that 24 and 18 kDa Oleosins were hydrolyzed in the extracted OBs, which contained many OB extrinsic proteins (i.e., lipoxygenase, β-conglycinin, γ-conglycinin, β-amylase, glycinin, Gly m Bd 30K (Bd 30K), and P34 probable thiol protease (P34)) as well as OB intrinsic proteins. In this study, some properties (specificity, optimal pH and temperature) of the proteases of 24 and 18 kDa Oleosins and the Oleosin hydrolysis in soybean germination were examined, and the high relationship between Bd 30K/P34 and the proteases was also discussed. The results showed (1) the proteases were OB extrinsic proteins, which had high specificity to hydrolyze 24 and 18 kDa Oleosins, and cleaved the specific peptide bonds to form limited hydrolyzed products; (2) 24 and 18 kDa Oleosins were not hydrolyzed in the absence of Bd 30K and P34 (or some Tricine-SDS-PAGE undetectable proteins); (3) the protease of 24 kDa Oleosin had strong...
