1. Two previously unknown amino acids have been identified, and purified from cells of Group N streptococci. The chemical structures and stereochemical configurations of N(5)-(1- carboxymethyl)ornithine and N(6)-(1-carboxymethyl)lysine have been confirmed by chiral syntheses and NMR-spectroscopy. 2. It has been established that the in vivo synthesis of these unusual compounds occurs via the NAD(P)H-dependent reductive condensation between pyruvic acid and the side-chain amino groups of ornithine and lysine. The synthase responsible for the biosynthesis of these novel amino acids has been purified (8000- fold) to homogeneity from cells of Streptococcus lactis K1. The physical and enzymatic properties of the enzyme have been partially defined. 3. The accumulation of sugars (glucose and galactose) by cells of Fusobacterium nucleatum 10953 is dependent upon the provision of glutamic acid, lysine or histidine. These fermentable amino acids provide the energy necessary for sugar transport, phosphorylation and synthesis of endogenous sugar polymer(s). The presence of the amino acids also inhibits the degradation of pre-formed polymer, but in the absence of glutamate, lysine or histidine endogenous polymer is fermented via the Embden-Meyerhof pathway. The concentrations of Na+ and NH4+ ion in the environment markedly affect the rates of sugar transport by resting cells of F. nucleatum. The biochemical roles of

National Institute of Health (NIH)
National Institute of Dental & Craniofacial Research (NIDCR)
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Dental & Craniofacial Research
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Zhang, Qiangmin; Gao, Feng; Peng, Hao et al. (2009) Crystal structures of Streptococcus suis mannonate dehydratase (ManD) and its complex with substrate: genetic and biochemical evidence for a catalytic mechanism. J Bacteriol 191:5832-7
Zhang, Qiangmin; Peng, Hao; Gao, Feng et al. (2009) Structural insight into the catalytic mechanism of gluconate 5-dehydrogenase from Streptococcus suis: Crystal structures of the substrate-free and quaternary complex enzymes. Protein Sci 18:294-303
Hall, Barry G; Pikis, Andreas; Thompson, John (2009) Evolution and biochemistry of family 4 glycosidases: implications for assigning enzyme function in sequence annotations. Mol Biol Evol 26:2487-97
Pikis, Andreas; Hess, Sonja; Arnold, Ingrid et al. (2006) Genetic requirements for growth of Escherichia coli K12 on methyl-alpha-D-glucopyranoside and the five alpha-D-glucosyl-D-fructose isomers of sucrose. J Biol Chem 281:17900-8
Thompson, John; Hess, Sonja; Pikis, Andreas (2004) Genes malh and pagl of Clostridium acetobutylicum ATCC 824 encode NAD+- and Mn2+-dependent phospho-alpha-glucosidase(s). J Biol Chem 279:1553-61
Rajan, Shyamala S; Yang, Xiaojing; Collart, Frank et al. (2004) Novel catalytic mechanism of glycoside hydrolysis based on the structure of an NAD+/Mn2+ -dependent phospho-alpha-glucosidase from Bacillus subtilis. Structure 12:1619-29
Yip, Vivian L Y; Varrot, Annabelle; Davies, Gideon J et al. (2004) An unusual mechanism of glycoside hydrolysis involving redox and elimination steps by a family 4 beta-glycosidase from Thermotoga maritima. J Am Chem Soc 126:8354-5
Xu, De-Qi; Thompson, John; Cisar, John O (2003) Genetic loci for coaggregation receptor polysaccharide biosynthesis in Streptococcus gordonii 38. J Bacteriol 185:5419-30
Cisar, J O; Xu, D Q; Thompson, J et al. (2000) An alternative interpretation of nanobacteria-induced biomineralization. Proc Natl Acad Sci U S A 97:11511-5