In molecular biology, the ELFV dehydrogenase family of enzymes include glutamate, leucine, phenylalanine and valine dehydrogenases. These enzymes are structurally and functionally related. They contain a Gly-rich region containing a conserved Lys residue, which has been implicated in the catalytic activity, in each case a reversible oxidative deamination reaction.
| Glutamate/Leucine/Phenylalanine/Valine dehydrogenase | |||||||||
|---|---|---|---|---|---|---|---|---|---|
 thermotoga maritima glutamate dehydrogenase mutant n97d, g376k | |||||||||
| Identifiers | |||||||||
| Symbol | ELFV_dehydrog | ||||||||
| Pfam | PF00208 | ||||||||
| Pfam clan | CL0063 | ||||||||
| InterPro | IPR006096 | ||||||||
| PROSITE | PDOC00071 | ||||||||
| SCOP2 | 1leh / SCOPe / SUPFAM | ||||||||
| |||||||||
| Glu/Leu/Phe/Val dehydrogenase, dimerisation domain | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Identifiers | |||||||||
| Symbol | ELFV_dehydrog_N | ||||||||
| Pfam | PF02812 | ||||||||
| SCOP2 | 1leh / SCOPe / SUPFAM | ||||||||
| |||||||||
Glutamate dehydrogenases EC 1.4.1.2, EC 1.4.1.3 and EC 1.4.1.4 (GluDH) are enzymes that catalyse the NAD- and/or NADP-dependent reversible deamination of L-glutamate into alpha-ketoglutarate.[1][2] GluDH isozymes are generally involved with either ammonia assimilation or glutamate catabolism. Two separate enzymes are present in yeasts: the NADP-dependent enzyme, which catalyses the amination of alpha-ketoglutarate to L-glutamate; and the NAD-dependent enzyme, which catalyses the reverse reaction [3] - this form links the L-amino acids with the Krebs cycle, which provides a major pathway for metabolic interconversion of alpha-amino acids and alpha-keto acids.[4]
Leucine dehydrogenase EC 1.4.1.9 (LeuDH) is a NAD-dependent enzyme that catalyses the reversible deamination of leucine and several other aliphatic amino acids to their keto analogues.[5] Each subunit of this octameric enzyme from Bacillus sphaericus contains 364 amino acids and folds into two domains, separated by a deep cleft. The nicotinamide ring of the NAD+ cofactor binds deep in this cleft, which is thought to close during the hydride transfer step of the catalytic cycle.
Phenylalanine dehydrogenase EC 1.4.1.20 (PheDH) is an NAD-dependent enzyme that catalyses the reversible deamidation of L-phenylalanine into phenyl-pyruvate.[6]
Valine dehydrogenase EC 1.4.1.8 (ValDH) is an NADP-dependent enzyme that catalyses the reversible deamidation of L-valine into 3-methyl-2-oxobutanoate.[7]
These enzymes contain two domains, an N-terminal dimerisation domain, and a C-terminal domain.[8]
References
edit- ^ Britton KL, Baker PJ, Rice DW, Stillman TJ (November 1992). "Structural relationship between the hexameric and tetrameric family of glutamate dehydrogenases". Eur. J. Biochem. 209 (3): 851–9. doi:10.1111/j.1432-1033.1992.tb17357.x. PMID 1358610.
- ^ Benachenhou-Lahfa N, Forterre P, Labedan B (April 1993). "Evolution of glutamate dehydrogenase genes: evidence for two paralogous protein families and unusual branching patterns of the archaebacteria in the universal tree of life". J. Mol. Evol. 36 (4): 335–46. doi:10.1007/bf00182181. PMID 8315654. S2CID 25117393.
- ^ Moye WS, Amuro N, Rao JK, Zalkin H (July 1985). "Nucleotide sequence of yeast GDH1 encoding nicotinamide adenine dinucleotide phosphate-dependent glutamate dehydrogenase". J. Biol. Chem. 260 (14): 8502–8. doi:10.1016/S0021-9258(17)39500-5. PMID 2989290.
- ^ Mavrothalassitis G, Tzimagiorgis G, Mitsialis A, Zannis V, Plaitakis A, Papamatheakis J, Moschonas N (May 1988). "Isolation and characterization of cDNA clones encoding human liver glutamate dehydrogenase: evidence for a small gene family". Proc. Natl. Acad. Sci. U.S.A. 85 (10): 3494–8. doi:10.1073/pnas.85.10.3494. PMC 280238. PMID 3368458.
- ^ Nagata S, Tanizawa K, Esaki N, Sakamoto Y, Ohshima T, Tanaka H, Soda K (December 1988). "Gene cloning and sequence determination of leucine dehydrogenase from Bacillus stearothermophilus and structural comparison with other NAD(P)+-dependent dehydrogenases". Biochemistry. 27 (25): 9056–62. doi:10.1021/bi00425a026. PMID 3069133.
- ^ Takada H, Yoshimura T, Ohshima T, Esaki N, Soda K (March 1991). "Thermostable phenylalanine dehydrogenase of Thermoactinomyces intermedius: cloning, expression, and sequencing of its gene". J. Biochem. 109 (3): 371–6. doi:10.1093/oxfordjournals.jbchem.a123388. PMID 1880121.
- ^ Tang L, Hutchinson CR (July 1993). "Sequence, transcriptional, and functional analyses of the valine (branched-chain amino acid) dehydrogenase gene of Streptomyces coelicolor". J. Bacteriol. 175 (13): 4176–85. doi:10.1128/jb.175.13.4176-4185.1993. PMC 204847. PMID 8320231.
- ^ Baker, P. J.; Turnbull, A. P.; Sedelnikova, S. E.; Stillman, T. J.; Rice, D. W. (1995). "A role for quaternary structure in the substrate specificity of leucine dehydrogenase". Structure. 3 (7): 693–705. doi:10.1016/S0969-2126(01)00204-0. PMID 8591046.