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N. S. Funtikova - One of the best experts on this subject based on the ideXlab platform.
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Effects of conditions for obtaining Sporangiospores of the inoculum on the morphology and productivity of the fungus Mucor circinelloides var. lusitanicus 12 M, a producer of γ-linolenic acid
Applied Biochemistry and Microbiology, 2008Co-Authors: N. S. Funtikova, I. S. MysyakinaAbstract:Effects of the lipid composition of Sporangiospores of the fungus Mucor circinelloides var. lusitanicus 12 M, obtained within diverse time frames using distinct nutrient media, on the morphology of the fungus in submerged cultures, the yield of the biomass, and its content of g-linolenic acid have been studied. The levels of base phospholipids and individual fractions of neutral lipids in Sporangiospores correlated with the character of their germination. The spores that were characterized by a high rate of germination and gave rise to a well-developed mycelium contained more phosphatidylcholine and phosphatidylserine, but the level of diacylglycerols was low. The increase in diacylglycerols, free fatty acids, and sterols in lipids of Sporangiospores of the inoculate was associated with deterioration in mycelium development, dimorphism, and a decreasing yield of the biomass of the fungus.
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Effects of conditions for obtaining Sporangiospores of the inoculum on the morphology and productivity of the fungus Mucor circinelloides var. lusitanicus 12 M, a producer of gamma-linolenic acid
Prikladnaia biokhimiia i mikrobiologiia, 2008Co-Authors: N. S. Funtikova, I S MysiakinaAbstract:Effects of lipid composition of Sporangiospores of the fungus Mucor circinelloides var. lusitanicus 12 M, obtained within diverse time frames using distinct nutritive media, on the morphology of the fungus in submerged cultures, the yield of the biomass, and its content of gamma-linolenic acid have been studied. The levels of base phospholipids and individual fractions of neutral lipids in Sporangiospores were correlated with the character of their germination. The spores characterized by a high rate of germination and giving rise to a well-developed mycelium contained more phosphatidylcholine and phosphatidylserine, but the level of diacylglycerols was low. An increase in diacylglycerols, free fatty acids, and sterols in lipids of Sporangiospores of the inoculate was associated with deterioration of the mycelium development, dimorphism, and lowering of the yield of the biomass of the fungus.
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Sporangiospore lipids of the mycelial fungus Mucor ramannianus incapable of dimorphic growth
Microbiology, 2007Co-Authors: I. S. Mysyakina, N. S. FuntikovaAbstract:Members of the species Mucor ramannianus are believed to be monomorphic. They grow only as a mycelium and are not capable of growth as budding cells, i.e., of dimorphic growth. In our study, we investigated the lipid composition of M. ramannianus Sporangiospores, which retained the capability of initiating mycelial growth in the course of long-term cultivation of the spore-forming mycelium. It was demonstrated that Sporangiospores contained high concentrations of triacylglycerides (TAG) in their reserve lipids and high concentrations of phosphatidylcholine (PC) in their membrane lipids; low concentrations of methylated ergosterol precursors were detected among sterols. On the basis of the data presented, in order to evaluate the potential of mucor fungi for yeastlike growth, it has been suggested to analyze the qualitative and quantitative characteristics of their Sporangiospore lipids and to consider the following criteria as the criteria of Sporangiospore capacity for giving rise to yeastlike growth upon spore germination: (1) the phosphatidylethanolamine/phosphatidylcholine (PE/PC) ratio; (2) the level of ergosterol and the ratio between the methylated and demethylated sterols; as well as (3) the ratios between phospholipids and glycolipids (PL/GL) and (4) between etherified and free sterols (ES/FS).
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Sporangiospores of the Fungus Mucor lusitanicus 12M: Correlation between Lipid Composition, Viability, and Morphology of Growth upon Germination
Microbiology, 2003Co-Authors: N. S. Funtikova, I. S. MysyakinaAbstract:We studied viability of Sporangiospores from a surface culture of the fungus Mucor lusitanicus 12M grown on wheat bran. With culture aging, the Sporangiospores exhibited a tendency toward dimorphic growth upon germination and then lost the ability to germinate. This correlated with changes in the Sporangiospore lipid composition, which involved a reduction in the total lipid pool and in the levels of reserve lipids and phospholipids in particular. We suggest that lipid catabolism in Sporangiospores causes their defectiveness in the senescent culture.
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Changes in the Lipid Composition of Mucor hiemalis Sporangiospores Related to the Age of the Spore-Forming Culture
Microbiology, 2003Co-Authors: I. S. Mysyakina, N. S. FuntikovaAbstract:Analysis of Sporangiospore lipids of the fungus Mucor hiemalis F-1156 showed that alterations occur in the content of fatty acids and individual classes of lipids during long-term cultivation (for about 20 days). The changes in the lipid composition related to the age of the spore-forming mycelium suggest an important role of Sporangiospore lipids in spore germination and in further development of the spherical cells formed in this processes. The M. hiemalis F-1156 Sporangiospores with a lipid pool exhausted during long-term cultivation can give rise to both mycelial and yeastlike growth.
I. S. Mysyakina - One of the best experts on this subject based on the ideXlab platform.
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Lipid composition of the spores of zygomycetous and ascomycetous fungi during cessation of the exogenous dormancy state
Microbiology, 2018Co-Authors: I. S. Mysyakina, Ya. E. Sergeeva, D. A. BokarevaAbstract:The composition of lipids and fatty acids was studied in the spores of exogenously dormant (spores 0) and germinating (spores G) spores in distilled water for Sporangiospores of zygomycetous fungi Cunninghamella echinulata VKM F-663 and Umbelopsis ramanniana VKM F-582 and for conidia of ascomycetous fungi Aspergillus tamarii VKM F-64 and A. sydowii VKM F-441. Compared to spores 0, the lipids of spores G contained higher shares of unsaturated fatty acids, lower levels of massive phospholipids (phosphatidylcholine and phosphatidylethanolamine), and elevated levels of phosphatidylglycerol and phosphatidic acid. The level of cardiolipin, the main phospholipid of the mitochondrial membranes, increased when the spores of both zygomycetes exited from the dormant state. While a certain increase in the content of free and esterified sterols in the neutral lipids of the slowly germinating U. ramanniana G spores was observed, germination of Sporangiospores and conidia of the studied fungi generally did not result in significant changes in the composition of the neutral lipid classes, which may be due to the fact that they are not the major reserve mobilized at the stage of exit from the dormant state.
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Lipid and elemental composition as indicators of the physiological state of Sporangiospores in Mucor hiemalis cultures of different ages
Microbiology, 2014Co-Authors: I. S. Mysyakina, Ya. E. Sergeeva, V. V. Sorokin, A. A. Ivashechkin, Nadezhda A. Kostrikina, E. P. FeofilovaAbstract:The number of Sporangiospores used as inocula may significantly affect the development of the morphogenetic programs in mucoraceous fungi, including manifestations of dimorphism. In order to assess the physiological state of Sporangiospores differing in their viability and germination patterns, lipid composition of Sporangiospores from 6-, 14-, and 20-day cultures of Mucor hiemalis F-1431 was determined and the element ratios in these spores (Ca/K and P/S) were measured using X-ray microanalysis. While the lipid composition of the “old” (20 days) and “young” (6 days) spores was generally similar, older spores contained no cerebrosides, had half the level of polar lipids and γ-linolenic acid, and also contained 6 times more monoacylglycerols and 2.5 times more phosphatidic acid. The ratio of esterified to free sterols (ES/FS) characterizing the sterol storage pool was lowest in the spores from 20-day cultures. X-ray microanalysis revealed the highest P/S ratio in 6-day spores and lowest ratio in 14-day ones. Mature 14-day spores had the highest Ca/K ratio, ten times exceeding that for the 20-day spores. Higher values of P/S and Ca/K ratios in young (ripening) spores than in old 20-day spores indicate their higher metabolic activity and correlate with their higher viability and mycelial type of germination. Together with the lipid characteristics, the Ca/K and P/S ratios are the parameters which may be used to develop the criteria for assessment of the physiological state of the cells, including viable fungal Sporangiospores. This complex may be also used to assess the capacity of mucoraceous fungi for dimorphism, including the species (M. hiemalis) for which this capacity has not been demonstrated previously.
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Effects of conditions for obtaining Sporangiospores of the inoculum on the morphology and productivity of the fungus Mucor circinelloides var. lusitanicus 12 M, a producer of γ-linolenic acid
Applied Biochemistry and Microbiology, 2008Co-Authors: N. S. Funtikova, I. S. MysyakinaAbstract:Effects of the lipid composition of Sporangiospores of the fungus Mucor circinelloides var. lusitanicus 12 M, obtained within diverse time frames using distinct nutrient media, on the morphology of the fungus in submerged cultures, the yield of the biomass, and its content of g-linolenic acid have been studied. The levels of base phospholipids and individual fractions of neutral lipids in Sporangiospores correlated with the character of their germination. The spores that were characterized by a high rate of germination and gave rise to a well-developed mycelium contained more phosphatidylcholine and phosphatidylserine, but the level of diacylglycerols was low. The increase in diacylglycerols, free fatty acids, and sterols in lipids of Sporangiospores of the inoculate was associated with deterioration in mycelium development, dimorphism, and a decreasing yield of the biomass of the fungus.
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Sporangiospore lipids of the mycelial fungus Mucor ramannianus incapable of dimorphic growth
Microbiology, 2007Co-Authors: I. S. Mysyakina, N. S. FuntikovaAbstract:Members of the species Mucor ramannianus are believed to be monomorphic. They grow only as a mycelium and are not capable of growth as budding cells, i.e., of dimorphic growth. In our study, we investigated the lipid composition of M. ramannianus Sporangiospores, which retained the capability of initiating mycelial growth in the course of long-term cultivation of the spore-forming mycelium. It was demonstrated that Sporangiospores contained high concentrations of triacylglycerides (TAG) in their reserve lipids and high concentrations of phosphatidylcholine (PC) in their membrane lipids; low concentrations of methylated ergosterol precursors were detected among sterols. On the basis of the data presented, in order to evaluate the potential of mucor fungi for yeastlike growth, it has been suggested to analyze the qualitative and quantitative characteristics of their Sporangiospore lipids and to consider the following criteria as the criteria of Sporangiospore capacity for giving rise to yeastlike growth upon spore germination: (1) the phosphatidylethanolamine/phosphatidylcholine (PE/PC) ratio; (2) the level of ergosterol and the ratio between the methylated and demethylated sterols; as well as (3) the ratios between phospholipids and glycolipids (PL/GL) and (4) between etherified and free sterols (ES/FS).
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Sporangiospores of the Fungus Mucor lusitanicus 12M: Correlation between Lipid Composition, Viability, and Morphology of Growth upon Germination
Microbiology, 2003Co-Authors: N. S. Funtikova, I. S. MysyakinaAbstract:We studied viability of Sporangiospores from a surface culture of the fungus Mucor lusitanicus 12M grown on wheat bran. With culture aging, the Sporangiospores exhibited a tendency toward dimorphic growth upon germination and then lost the ability to germinate. This correlated with changes in the Sporangiospore lipid composition, which involved a reduction in the total lipid pool and in the levels of reserve lipids and phospholipids in particular. We suggest that lipid catabolism in Sporangiospores causes their defectiveness in the senescent culture.
Co Omoifo - One of the best experts on this subject based on the ideXlab platform.
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ISSN 1684–5315 © 2009 Academic Journals
2016Co-Authors: Co OmoifoAbstract:Sporangiospore-to-yeast conversion: Model for morphogenesi
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Rhizopus stolonifer exhibits dimorphism
African Journal of Biotechnology, 2011Co-Authors: Co OmoifoAbstract:This study showed that multiple morphologies could be induced from Sporangiospores of Rhizopus stolonifer in minimal medium. These included moniliform hyphae, septate hyphae and terminal budding yeast cells. When considered along the normal coenocytic filamentous growth form, the study showed that R. stolonifer could be polymorphic. Key words : Rhizopus stolonifer, polymorphic, multiple morphologies.
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Effect of extracellular calcium chloride on Sporangiospore-yeast transformation of Rhizopus stolonifer
African Journal of Biotechnology, 2011Co-Authors: Co OmoifoAbstract:Previous studies showed that zinc and myoinositol, which are intracellular, serve as components of signalling elements in many eukaryotes, and participate in stimulating the induction and proliferation of yeast cells from Sporangiospores of fungi. It was thought that a transmembrane-pH-gradient, similar to what is obtained in bacterial mitochondrion or proton-substrate symport in yeasts, permitted influx/efflux of materials into the cell that triggered the induction and subsequent proliferation of yeast cells. To examine this model further, this study evaluated the ability of Sporangiospores of Rhizopus stolonifer to undergo morphogenetic transformation in the presence of different levels of extracellular calcium (0.0, 0.20, 0.25, 0.50, 1.0, 1.5 and 1.8 mM). It was found that calcium supported yeast induction and proliferation to varying extent. Ca 2+ at 0.50 and1.8 mM, which was outstanding, was compared with broth treatment at 0.25 mM ZnSO 4 : pH 4.5 which gave optimum biomass in a previous study. Medium pH was further varied: pH 4.2, 4.5 and 5.0. The results showed that there was interaction between the level of divalent cations and pH. At all levels tested, Ca 2+ was better stimulatory than Zn 2+ . Direct induced yeast cell count, which eliminated possible impact of protoplasts and calcium phosphate precipitate on optical density measurements, made these results more valid. Treatment at 0.50 mM Ca 2+ : pH 5.0 gave the most profound result. This was therefore chosen for further biochemical work. Key words : Rhizopus stolonifer, synthetic broth, dimorphism, extracellular Ca 2+ , Sporangiospores, induced yeast cells.
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DOI: 10.5897/AJB09.787
2011Co-Authors: Co OmoifoAbstract:Effect of extracellular calcium chloride on Sporangiospore-yeast transformation of Rhizopus stolonife
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Sporangiospore to yeast conversion model for morphogenesis
African Journal of Biotechnology, 2009Co-Authors: Co OmoifoAbstract:This report reviewed the specific characteristics of Mucor circinelloides in solid cultures and its capacity for multiple anamorphic expressions in synthetic broth, including holoblastic, holothallic, enterothallic conidia, and vesicular conidia head group as well as yeast cells. Attempt was made to show that the sequence of events in the conversion process, with inherent cytosolic nucleation and protoplast formation, to terminal budding yeast cell would serve as a model for studying morphogenetic transformation in the fungi.
Jinhyeuk Kwon - One of the best experts on this subject based on the ideXlab platform.
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Soft Rot of Rhizopus oryzae as a Postharvest Pathogen of Banana Fruit in Korea.
Mycobiology, 2012Co-Authors: Jinhyeuk Kwon, Jae-san Ryu, Tran Thi Phuong Chi, Shun-shan Shen, Okhee ChoiAbstract:Soft rot on banana fruit caused by Rhizopus oryzae was identified for the first time in Korea. Colonies were white to light brown and formed numerous Sporangiospores. Optimum temperature for mycelial growth was 30℃. Sporangia were globose and 30~200 µm. Sporangiophores were usually straight, 8~20 µm, and rhizoids usually in groups of 3~5. Columella were globose to sub-globose and 90~110 µm. Sporangiospores were sub-globose or oval and 4~10 µm. Based on its mycological characteristics, molecular analysis, and pathogenicity to host plants, this fungus was identified as Rhizopus oryzae Went & Prisen Geerligs. This is the first report of soft rot on banana caused by Rhizopus oryzae in Korea.
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occurrence of rhizopus soft rot on rubus crataegifolius caused by rhizopus stolonifer in korea
Research in Plant Disease, 2008Co-Authors: Jinhyeuk KwonAbstract:Rhizopus soft rot caused by Rhizopus stolonifer on June, 2008 occurred on Rubus crataegifolius Bunge in the box at Jinju City Wholesale Market of Agricultural Products at Gyeongnam province in Korea. The infected fruits were rapidly water-soaked, softened, black and eventually rotted. The symptoms occurred after infecting wounds at harvest time. The colony were white to light brown, formed much Sporangiospores. The optimum temperature of the fungus on potato dextrose agar was . Sporangiophores were in width. Sporangia were globose or hemispheric, white at first and gradually to black, and in size. Columella were hemispheric, and in size. Sporangiospores were irregular round or oval, brownishblack and in size. On the basis of symptom, mycological characteristics and pathogenicity of the fungus, the causal fungus was identified as Rhizopus stolonifer. This is the first report of Rhizopus soft rot by R. stolonifer on R. crataegifolius in Korea.
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occurrence of rhizopus soft rot on musa sapientum caused by rhizopus stolonifer in korea
The Korean Journal of Mycology, 2007Co-Authors: Jinhyeuk KwonAbstract:Rhizopus soft rot caused by Rhizopus stolonifer occurred on banana (Musa sapientum) in the box at Jinju City Wholesale Market of Agricultural Products at Gyeongnam province in Korea. The infected fruits were rapidly water-soaked, softened, blackened and eventually rotted. They were infected from wounds at harvest time. The colony of the isolate from the infected fruit was white to light brown and formed many Sporangiospores. The optimum growth temperature of the fungus on potato dextrose agar was . Sporangiophores were in width. Sporangia were globose or hemispheric, white at first and changed gradually to black, and in size. Columella were hemispheric, and in size. Sporangiospores were irregular round or oval, brownish-black and in size. On the basis of symptom, mycological characteristics and pathogenicity to banana, the causal fungus was identified as Rhizopus stolonifer. This is the first report of Rhizopus soft rot by R. stolonifer on banana in Korea.
Soo Chan Lee - One of the best experts on this subject based on the ideXlab platform.
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Sporangiospore size dimorphism is linked to virulence of Mucor circinelloides
PLoS pathogens, 2011Co-Authors: María Cervantes, Santiago Torres-martínez, Rosa M. Ruiz-vázquez, Deborah J. Springer, Teun Boekhout, Joseph Heitman, Soo Chan LeeAbstract:Mucor circinelloides is a zygomycete fungus and an emerging opportunistic pathogen in immunocompromised patients, especially transplant recipients and in some cases otherwise healthy individuals. We have discovered a novel example of size dimorphism linked to virulence. M. circinelloides is a heterothallic fungus: (+) sex allele encodes SexP and (−) sex allele SexM, both of which are HMG domain protein sex determinants. M. circinelloides f. lusitanicus (Mcl) (−) mating type isolates produce larger asexual Sporangiospores that are more virulent in the wax moth host compared to (+) isolates that produce smaller less virulent Sporangiospores. The larger Sporangiospores germinate inside and lyse macrophages, whereas the smaller Sporangiospores do not. sexMΔ mutants are sterile and still produce larger virulent Sporangiospores, suggesting that either the sex locus is not involved in virulence/spore size or the sexP allele plays an inhibitory role. Phylogenetic analysis supports that at least three extant subspecies populate the M. circinelloides complex in nature: Mcl, M. circinelloides f. griseocyanus, and M. circinelloides f. circinelloides (Mcc). Mcc was found to be more prevalent among clinical Mucor isolates, and more virulent than Mcl in a diabetic murine model in contrast to the wax moth host. The M. circinelloides sex locus encodes an HMG domain protein (SexP for plus and SexM for minus mating types) flanked by genes encoding triose phosphate transporter (TPT) and RNA helicase homologs. The borders of the sex locus between the three subspecies differ: the Mcg sex locus includes the promoters of both the TPT and the RNA helicase genes, whereas the Mcl and Mcc sex locus includes only the TPT gene promoter. Mating between subspecies was restricted compared to mating within subspecies. These findings demonstrate that spore size dimorphism is linked to virulence of M. circinelloides species and that plasticity of the sex locus and adaptations in pathogenicity have occurred during speciation of the M. circinelloides complex.