Vit A Mashabela GT Blankenfeldt W Seebeck FP 2015 The ubiquitous sulfur metabolite ergothioneine is biosynthesized by oxidative attachment of a sulfur atom to the imidazole ring of Nα-trimethylhistidine. Most actinobacteria, including Mycobacterium tuberculosis, use γ-glutamyl cysteine as a sulfur donor. In subsequent steps the carbon scaffold of γ-glutamyl cysteine is removed by the glutamine amidohydrolase EgtC and the β-lyase EgtE. We determined the crystal structure of EgtC from Mycobacterium smegmatis in complex with its physiological substrate. The set of active site residues that define substrate specificity in EgtC are highly conserved, even in homologues that are not involved in ergothioneine production. This conservation is compounded by the phylogenetic distribution of EgtC-like enzymes indicates that their last common ancestor might have emerged for a purpose other than ergothioneine production. application/pdf https://sonar.ch/global/documents/150049 eng info:eu-repo/semantics/altIdentifier/doi/10.1002/cbic.201500168 info:eu-repo/semantics/altIdentifier/pmid/26079795 info:eu-repo/semantics/openAccess Chembiochem : a European journal of chemical biology. - 2015 biosynthesis enzymes ergothioneine hydrolases mycobacteria sulfoxide stereochemistry Amidohydrolases Amino Acid Sequence Binding Sites Conserved Sequence Ergothioneine Glutamine Models, Molecular Molecular Sequence Data Mycobacterium smegmatis Phylogeny Protein Conformation Sequence Alignment Substrate Specificity Sulfoxides Structure of the Ergothioneine-Biosynthesis Amidohydrolase EgtC. http://purl.org/coar/resource_type/c_6501