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A M Edwards - One of the best experts on this subject based on the ideXlab platform.
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the crystal structure of hypothetical protein mth1491 from methanobacterium thermoautotrophicum
Protein Science, 2002Co-Authors: Dinesh Christendat, V Saridakis, Ponni A Kumar, Xiaohui Xu, A Semesi, Andzrej Joachimiak, C H Arrowsmith, A M EdwardsAbstract:As part of our structural proteomics initiative, we have determined the crystal structure of MTH1491, a previously uncharacterized hypothetical protein from Methanobacterium thermoautotrophicum. MTH1491 is one of numerous structural genomics targets selected in a genome-wide survey of uncharacterized proteins. It belongs to a family of proteins whose biological function is not known. The crystal structure of MTH1491, the first structure for this family of proteins, consists of an overall five-stranded parallel β-sheet with strand order 51234 and flanking helices. The oligomeric form of this molecule is a trimer as seen from both crystal contacts and gel filtration studies. Analysis revealed that the structure of MTH1491 is similar to that of dehydrogenases, Amidohydrolases, and oxidoreductases. Using a combination of sequence and structural analyses, we showed that MTH1491 does not belong to either the dehydrogenase or the Amidohydrolase superfamilies of proteins.
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the crystal structure of hypothetical protein mth1491 from methanobacterium thermoautotrophicum
Protein Science, 2002Co-Authors: Dinesh Christendat, V Saridakis, Ponni A Kumar, A Semesi, Andzrej Joachimiak, C H Arrowsmith, A M Edwards, Youngchang KimAbstract:As part of our structural proteomics initiative, we have determined the crystal structure of MTH1491, a previously uncharacterized hypothetical protein from Methanobacterium thermoautotrophicum. MTH1491 is one of numerous structural genomics targets selected in a genome-wide survey of uncharacterized proteins. It belongs to a family of proteins whose biological function is not known. The crystal structure of MTH1491, the first structure for this family of proteins, consists of an overall five-stranded parallel beta-sheet with strand order 51234 and flanking helices. The oligomeric form of this molecule is a trimer as seen from both crystal contacts and gel filtration studies. Analysis revealed that the structure of MTH1491 is similar to that of dehydrogenases, Amidohydrolases, and oxidoreductases. Using a combination of sequence and structural analyses, we showed that MTH1491 does not belong to either the dehydrogenase or the Amidohydrolase superfamilies of proteins.
Takashi Tokunaga - One of the best experts on this subject based on the ideXlab platform.
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partial purification and characterization of the porcine brain enzyme hydrolyzing and synthesizing anandamide
Journal of Biological Chemistry, 1995Co-Authors: Natsuo Ueda, Yuko Kurahashi, Shozo Yamamoto, Takashi TokunagaAbstract:Abstract Anandamide (arachidonylethanolamide) is known as an endogenous agonist for cannabinoid receptors. An Amidohydrolase, which hydrolyzed anandamide, was solubilized from the microsomal fraction of porcine brain with 1% Triton X-100. The enzyme was partially purified by Phenyl-5PW hydrophobic chromatography to a specific activity of approximately 0.37 μmol/min/mg of protein at 37°C. As assayed with 14C-labeled substrates, the apparent K value for anandamide was 60 μM, and anandamide was more active than ethanolamides of linoleic, oleic, and palmitic acids. Ceramidase and protease activities were not detected in our enzyme preparation. The purified enzyme also synthesized anandamide from free arachidonic acid in the presence of a high concentration of ethanolamine with a specific activity of about 0.16 μmol/min/mg of protein at 37°C. On the basis of cochromatographies, pH dependence, heat inactivation, and effects of inhibitors such as arachidonyl trifluoromethyl ketone, p-chloromercuribenzoic acid, diisopropyl fluorophosphate, and phenylmethylsulfonyl fluoride, it was suggested that the anandamide Amidohydrolase and synthase activities were attributable to a single enzyme protein.
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partial purification and characterization of the porcine brain enzyme hydrolyzing and synthesizing anandamide
Journal of Biological Chemistry, 1995Co-Authors: Natsuo Ueda, Yuko Kurahashi, Shozo Yamamoto, Takashi TokunagaAbstract:Anandamide (arachidonylethanolamide) is known as an endogenous agonist for cannabinoid receptors. An Amidohydrolase, which hydrolyzed anandamide, was solubilized from the microsomal fraction of porcine brain with 1% Triton X-100. The enzyme was partially purified by Phenyl-5PW hydrophobic chromatography to a specific activity of approximately 0.37 mumol/min/mg of protein at 37 degrees C. As assayed with 14C-labeled substrates, the apparent Km value for anandamide was 60 microM, and anandamide was more active than ethanolamides of linoleic, oleic, and palmitic acids. Ceramidase and protease activities were not detected in our enzyme preparation. The purified enzyme also synthesized anandamide from free arachidonic acid in the presence of a high concentration of ethanolamine with a specific activity of about 0.16 mumol/min/mg of protein at 37 degrees C. On the basis of cochromatographies, pH dependence, heat inactivation, and effects of inhibitors such as arachidonyl trifluoromethyl ketone, p-chloromercuribenzoic acid, diisopropyl fluorophosphate, and phenylmethylsulfonyl fluoride, it was suggested that the anandamide Amidohydrolase and synthase activities were attributable to a single enzyme protein.
Andreas Schwienhorst - One of the best experts on this subject based on the ideXlab platform.
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an active site tyrosine residue is essential for Amidohydrolase but not for esterase activity of a class 2 histone deacetylase like bacterial enzyme
Biochemical Journal, 2007Co-Authors: Kristin Moreth, Daniel Riester, Christian Hildmann, Rene Hempel, Dennis Wegener, Andreas Schober, Andreas SchwienhorstAbstract:HDACs (histone deacetylases) are considered to be among the most important enzymes that regulate gene expression in eukaryotic cells acting through deacetylation of ϵ-acetyl-lysine residues within the N-terminal tail of core histones. In addition, both eukaryotic HDACs as well as their bacterial counterparts were reported to also act on non-histone targets. However, we are still far from a comprehensive understanding of the biological activities of this ancient class of enzymes. In the present paper, we studied in more detail the esterase activity of HDACs, focussing on the HDAH (histone deacetylase-like Amidohydrolase) from Bordetella/Alcaligenes strain FB188. This enzyme was classified as a class 2 HDAC based on sequence comparison as well as functional data. Using chromogenic and fluorogenic ester substrates we show that HDACs such as FB188 HDAH indeed have esterase activity that is comparable with those of known esterases. Similar results were obtained for human HDAC1, 3 and 8. Standard HDAC inhibitors were able to block both activities with similar IC50 values. Interestingly, HDAC inhibitors such as suberoylanilide hydroxamic acid (SAHA) also showed inhibitory activity against porcine liver esterase and Pseudomonas fluorescens lipase. The esterase and the Amidohydrolase activity of FB188 HDAH both appear to have the same substrate specificity concerning the acyl moiety. Interestingly, a Y312F mutation in the active site of HDAH obstructed Amidohydrolase activity but significantly improved esterase activity, indicating subtle differences in the mechanism of both catalytic activities. Our results suggest that, in principle, HDACs may have other biological roles besides acting as protein deacetylases. Furthermore, data on HDAC inhibitors affecting known esterases indicate that these molecules, which are currently among the most promising drug candidates in cancer therapy, may have a broader target profile requiring further exploration.
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A New Amidohydrolase from Bordetella or Alcaligenes Strain FB188 with Similarities to Histone Deacetylases
Journal of bacteriology, 2004Co-Authors: Christian Hildmann, Daniel Riester, Dennis Wegener, Milena Ninkovic, Rüdiger Dietrich, Thomas Zimmermann, Olwen M Birch, Christine Dr. Bernegger, Peter Loidl, Andreas SchwienhorstAbstract:The full-length gene encoding the histone deacetylase (HDAC)-like Amidohydrolase (HDAH) from Bordetella or Alcaligenes (Bordetella/Alcaligenes) strain FB188 (DSM 11172) was cloned using degenerate primer PCR combined with inverse-PCR techniques and ultimately expressed in Escherichia coli. The expressed enzyme was biochemically characterized and found to be similar to the native enzyme for all properties examined. Nucleotide sequence analysis revealed an open reading frame of 1,110 bp which encodes a polypeptide with a theoretical molecular mass of 39 kDa. Interestingly, peptide sequencing disclosed that the N-terminal methionine is lacking in the mature wild-type enzyme, presumably due to the action of methionyl aminopeptidase. Sequence database searches suggest that the new Amidohydrolase belongs to the HDAC superfamily, with the closest homologs being found in the subfamily assigned acetylpolyamine Amidohydrolases (APAH). The APAH subfamily comprises enzymes or putative enzymes from such diverse microorganisms as Pseudomonas aeruginosa, Archaeoglobus fulgidus, and the actinomycete Mycoplana ramosa (formerly M. bullata). The FB188 HDAH, however, is only moderately active in catalyzing the deacetylation of acetylpolyamines. In fact, FB188 HDAH exhibits significant activity in standard HDAC assays and is inhibited by known HDAC inhibitors such as trichostatin A and suberoylanilide hydroxamic acid (SAHA). Several lines of evidence indicate that the FB188 HDAH is very similar to class 1 and 2 HDACs and contains a Zn2+ ion in the active site which contributes significantly to catalytic activity. Initial biotechnological applications demonstrated the extensive substrate spectrum and broad optimum pH range to be excellent criteria for using the new HDAH from Bordetella/Alcaligenes strain FB188 as a biocatalyst in technical biotransformations, e.g., within the scope of human immunodeficiency virus reverse transcriptase inhibitor synthesis.
C H Arrowsmith - One of the best experts on this subject based on the ideXlab platform.
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the crystal structure of hypothetical protein mth1491 from methanobacterium thermoautotrophicum
Protein Science, 2002Co-Authors: Dinesh Christendat, V Saridakis, Ponni A Kumar, Xiaohui Xu, A Semesi, Andzrej Joachimiak, C H Arrowsmith, A M EdwardsAbstract:As part of our structural proteomics initiative, we have determined the crystal structure of MTH1491, a previously uncharacterized hypothetical protein from Methanobacterium thermoautotrophicum. MTH1491 is one of numerous structural genomics targets selected in a genome-wide survey of uncharacterized proteins. It belongs to a family of proteins whose biological function is not known. The crystal structure of MTH1491, the first structure for this family of proteins, consists of an overall five-stranded parallel β-sheet with strand order 51234 and flanking helices. The oligomeric form of this molecule is a trimer as seen from both crystal contacts and gel filtration studies. Analysis revealed that the structure of MTH1491 is similar to that of dehydrogenases, Amidohydrolases, and oxidoreductases. Using a combination of sequence and structural analyses, we showed that MTH1491 does not belong to either the dehydrogenase or the Amidohydrolase superfamilies of proteins.
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the crystal structure of hypothetical protein mth1491 from methanobacterium thermoautotrophicum
Protein Science, 2002Co-Authors: Dinesh Christendat, V Saridakis, Ponni A Kumar, A Semesi, Andzrej Joachimiak, C H Arrowsmith, A M Edwards, Youngchang KimAbstract:As part of our structural proteomics initiative, we have determined the crystal structure of MTH1491, a previously uncharacterized hypothetical protein from Methanobacterium thermoautotrophicum. MTH1491 is one of numerous structural genomics targets selected in a genome-wide survey of uncharacterized proteins. It belongs to a family of proteins whose biological function is not known. The crystal structure of MTH1491, the first structure for this family of proteins, consists of an overall five-stranded parallel beta-sheet with strand order 51234 and flanking helices. The oligomeric form of this molecule is a trimer as seen from both crystal contacts and gel filtration studies. Analysis revealed that the structure of MTH1491 is similar to that of dehydrogenases, Amidohydrolases, and oxidoreductases. Using a combination of sequence and structural analyses, we showed that MTH1491 does not belong to either the dehydrogenase or the Amidohydrolase superfamilies of proteins.
Senlin Shen - One of the best experts on this subject based on the ideXlab platform.
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structure ofarabidopsis thaliana n6 methyl amp deaminase adal with bound gmp and imp and implications forn6 methyl amp recognition and processing
RNA Biology, 2019Co-Authors: Dong Zhang, Hongbo Nie, Senlin ShenAbstract:Arabidopsis thaliana aminohydrolase (AtADAL) has been shown to be involved in the metabolism of N6-methyl-AMP, a proposed intermediate during m6A-modified RNA metabolism, which can be subsequently ...