title: Enzymatic production of enantiopure amino acids from mono-substituted hydantoin substrates.
abstract: Biocatalytic conversion of 5-substituted hydantoin derivatives is an efficient method for the production of unnatural enantiomerically pure amino acids. The enzymes required to carry out this hydrolysis occur in a wide variety of eubacterial species each of which exhibit variations in substrate selectivity, enantiospecificity, and catalytic efficiency. Screening of the natural environment for bacterial strains capable of utilizing hydantoin as a nutrient source (as opposed to rational protein design of known enzymes) is a cost-effective and valuable approach for isolating microbial species with novel hydantoin-hydrolysing enzyme systems. Once candidate microbial isolates have been identified, characterization and optimization of the activity of target enzyme systems can be achieved by subjecting the hydantoin-hydrolysing system to physicochemical manipulations aimed at the enzymes activity within the natural host cells, expressed in a heterologous host, or as purified enzymes. The latter two options require knowledge of the genes encoding for the hydantoin-hydrolysing enzymes. This chapter describes the methods that can be used in conducting such development of hydantoinase-based biocatalytic routes for production of target amino acids.
authors.affiliation: Department of Biochemistry, Microbiology and Biotechnology, Rhodes University, Grahanstown, South Africa.
authors.forename: Gwynneth F
authors.initials: GF
authors.lastname: Matcher
authors.forename: Rosemary A
authors.initials: RA
authors.lastname: Dorrington
authors.forename: Stephanie G
authors.initials: SG
authors.lastname: Burton
mesh_terms: D000581:Amidohydrolases / Q000378:metabolism*; D000596:Amino Acids / Q000096:biosynthesis*; D006827:Hydantoins / Q000378:metabolism*; D013237:Stereoisomerism; D013379:Substrate Specificity
chemical_list: D000596:Amino Acids; D006827:Hydantoins; D000581:Amidohydrolases; C451299:N-carbamoylamino acid amidohydrolase; C020047:dihydropyrimidinase