4.1.1.11 evolution L-aspartate alpha-decarboxylase belongs to a class of pyruvoyl dependent enzymes 728571 4.1.1.11 evolution Salmonella enterica and Corynebacterium glutamicum L-aspartate-alpha-decarboxylases represent two different classes of homologues of these enzymes. Class I homologues require PanM for activation, while class II self cleave in the absence of PanM. Computer modeling of conserved amino acids using structure coordinates of PanM and L-aspartate-alpha-decarboxylase available in the protein data bank (RCSB PDB) reveal a putative site of interactions, analysis of self-cleavage mechanism of L-aspartate-alpha-decarboxylases. Phylogenetic distribution of prokaryotic L-aspartate-alpha-decarboxylase and PanM proteins, distribution of the two classes of PanD in the prokaryotes, overview -, 747435 4.1.1.11 evolution the enzyme is a member of a small class of pyruvoyl-dependent decarboxylases, in which the enzyme-bound pyruvoyl cofactor is generated via the autocatalytic rearrangement of a serine residue via an ester intermediate 726617 4.1.1.11 evolution the enzyme is a member of the small class of pyruvoyl-dependent enzymes, which contain a covalently-bound pyruvoyl cofactor -, 728266 4.1.1.11 evolution there are two primary types of ADCs produced from living organisms. One type is an insect ADC, which uses pyridoxal 5'-phosphate (PLP) as a cofactor. The other is bacterial ADC, which uses pyruvate as a cofactor -, 749207 4.1.1.11 evolution TK1814 homologues are distributed in a wide range of archaea and may be responsible for beta-alanine biosynthesis in these organisms. The GAD-type proteins from bacteria and those from plants, fungi, and yeast are actually GADs, as diverse members of this clade have been experimentally shown to display GAD activity. The six members of GAD-type proteins from mammals and acari (an arachnid subclass) are proven to be authentic GADs, but GADL1 from mammals and GAD-type proteins from insects within this clade have been shown to be ADCs and do not harbor the corresponding Asn residues that are important for recognition of gamma-carboxylate of Glu in human GAD65 (Asn203 in human GAD65). The ADC-type proteins from bacteria can be expected to function as ADCs, but none of the ADC-type proteins from hyperthermophilic bacteria (from Aquifex aeolicus) or from archaea have been examined -, 748086 4.1.1.11 malfunction a mutation in the aspartate decarboxylase gene (BmADC) causes melanized pupae with melanization specifically only at the pupal stage, the bp mutant phenotype. In the bp mutant, a SINE-like transposon insertion causes a sharp reduction in BmADC transcript levels in bp mutants, leading to deficiency of beta-alanine and N-beta-alanyl dopamine (NBAD), but accumulation of dopamine. Enzyme knockout also leads to the melanic pupae. The color pattern is reverted to that of the wild-type silkworms following injection of beta-alanine into bp mutants. Larvaeal bp phenotype, overview. Absence of beta-alanine and excessive accumulation of dopamine in the bp mutant 749304 4.1.1.11 malfunction ADC suppression favors formation of melanic pigment with a decrease in protein cross-linking 714398 4.1.1.11 malfunction an in vivo-selected pyrazinoic acid-resistant Mycobacterium tuberculosis strain harbors a missense mutation in the aspartate decarboxylase PanD. Mice infected with wild-type Mycobacterium tuberculosis are treated with pyrazinoic acid (POA), and POA-resistant colonies are confirmed for pyrazinamide (PZA) and POA resistance. Genome sequencing reveals that 82% and 18% of the strains contain missense mutations in panD and clpC1, respectively. POA/PZA resistance-conferring panD mutations are observed in POA-treated mice but not yet among clinical strains isolated from PZA-treated human patients 746598 4.1.1.11 malfunction both regulatory protein PanZ overexpression-linked beta-alanine auxotrophy and pentyl pantothenamide toxicity are due to formation of the PanDZ complex between enzyme PanD and effector protein PanZ. Formation of such a complex between activated aspartate decarboxylase (PanD) and PanZ leads to sequestration of the pyruvoyl cofactor as a ketone hydrate and demonstrates that both PanZ overexpression-linked beta-alanine auxotrophy and pentyl pantothenamide toxicity are due to formation of this complex. Substitution of the Escherichia coli panD for the noninteracting Bacillus panD suppresses the phenotype 747128 4.1.1.11 malfunction gene disruption of TK1814 results in a strain that cannot grow in standard medium. Addition of beta-alanine, 4'-phosphopantothenate, or CoA complements the growth defect, whereas gamma-aminobutyrate (GABA) cannot complement -, 748086 4.1.1.11 malfunction protein PanZ is essential for activation of the zymogen PanD to form ADC in vivo, and its deletion leads to beta-alanine auxotrophy 747497 4.1.1.11 malfunction the Glu56Ser mutation improves the enzymatic activity and catalytic stability of L-aspartate alpha-decarboxylase for an efficient beta-alanine production. The E56S mutant shows an approximately 1.4fold increased residual activity compared with the wild-type during 2 h reaction at 37°C, suggesting that the E56S mutation attenuated the mechanism-based inactivation of the enzyme -, 749207 4.1.1.11 malfunction when expressed in the Salmonella enterica DELTApanM strain, all panD homologues from bacteria that also contain a panM gene (Salmonella enterica, Klebsiella pneumoniae, Pseudomonas aeruginosa) fail to restore growth on minimal medium -, 747435 4.1.1.11 metabolism enzyme PanD is responsible for the production of beta-alanine in the pantothenate biosynthesis pathway. The production of beta-alanine is feedback-regulated by the PanZ-AcCoA complex 747128 4.1.1.11 metabolism L-aspartate alpha-decarboxylase catalyzes the conversion of aspartate to beta-alanine in the pantothenate pathway, which is critical for the growth of Mycobacterium tuberculosis 728571 4.1.1.11 metabolism the enzyme catalyzes the first step in the biosynthetic pathway of pantothenate and coenzyme A, overview -, 728266 4.1.1.11 metabolism the enzyme catalyzes the first step in the biosynthetic pathway of pantothenate and coenzyme A, pathway overview 726592 4.1.1.11 metabolism the enzyme is involved in the melanin metabolism pathway and in the melanin metabolism from dopamine to N-beta-alanyl dopamine (NBAD) 749304 4.1.1.11 metabolism the structure of the PanD/PanZ protein complex reveals negative feedback regulation of pantothenate biosynthesis by coenzyme A, regulatory model whereby the mature enzyme activity is limited and regulated by the concentration of CoA in the cell. Inhibition of mature enzyme catalysis reveals a second global role for PanZ in regulation of pantothenate biosynthesis. Such inhibitory activity is actually the primary metabolic role of PanZ, although the activation is also clearly essential 747497 4.1.1.11 additional information homology modeling and substrate docking, evaluation of potential substrate interacting residues, overview 727622 4.1.1.11 additional information NMR analysis of the PanD-PanZ-AcCoA complex 747497 4.1.1.11 additional information PanD-PanZ complex three-dimensional structure analysis, overview 747128 4.1.1.11 additional information regulatory mechanisms for PanD activation and inactivation in vivo, overview 726873 4.1.1.11 additional information role for Thr57 in the activation of the enzyme, its first role is that it acts as a general acid to support the formation of the ester intermediate by supporting the formation of the negative charge in the oxyoxazolidine intermediate, the second role is that after formation of the ester intermediate it acts as a general base to deprotonate the alpha-proton of Ser25, leading to chain cleavage and the formation of a dehydroalanine residue. Neither Tyr58 nor Tyr22 is required for the activation reaction, overview 726592 4.1.1.11 additional information structural homology modeling BsADC using the Escherichia coli ADC structure, PDB ID 1PQE, as template -, 749207 4.1.1.11 additional information the ancillary protein PanM (formerly YhhK) is required in vitro and in vivo for cleavage of the L-aspartate-alpha-decarboxylase zymogen -, 747435 4.1.1.11 additional information the enzyme active site is formed by the interface of a dimer, with relatively small volume. This cleft can support only molecules of relatively small size 728571 4.1.1.11 additional information the enzyme PanD is synthesized as pro-PanD, which undergoes an auto-proteolytic cleavage at residue Ser25 to yield the catalytic pyruvoyl moiety of the enzyme 728327 4.1.1.11 additional information the L-aspartate-alpha-decarboxylase zymogen from Corynebacterium glutamicum does not require PanM to process its own maturation -, 747435 4.1.1.11 additional information three key amino acid residues, R54, Y58, and R3, of L-aspartate alpha-decarboxylase act remotely from its cleavage site for its functional self-cleavage as well as for its catalytic activity. Highly conserved R54 residue contributes to the enzyme substrate specificity, and the highly conserved Y58 residue acts as the proton donor in the decarboxylation reaction. R54 and Y58 residues are also related with the self-cleavage process. The R54 and Y58 residues also block the formation of the active pyruvoyl cofactor, therefore the R54 and Y58 residues are assisting the R3 residue in the ADC self-cleavage process -, 727234 4.1.1.11 physiological function aspartate alpha-decarboxylase is a pyruvoyl-dependent decarboxylase required for the production of beta-alanine in the bacterial pantothenate (vitamin B5) biosynthesis pathway 726592 4.1.1.11 physiological function enzyme BmADC plays a crucial role in melanin metabolism and in the pigmentation pattern of the silkworm pupal stage 749304 4.1.1.11 physiological function L-aspartate alpha-decarboxylase is the key enzyme that catalyzes the decarboxylation of L-aspartate to beta-alanine, the only naturally occurring beta-amino acid -, 749207 4.1.1.11 physiological function regulation of PanD by PanZ allows these organisms to closely regulate production of beta-alanine and hence pantothenate in response to metabolic demand in host gut flora, where pantothenate is abundant -, 728266 4.1.1.11 physiological function the enzyme is a a glutamate decarboxylase (GAD) homologue encoded by gene TK1814. The recombinant bifunctional TK1814 protein displays not only GAD activity but also ADC activity using pyridoxal 5'-phosphate as a cofactor. The GAD activity of TK1814 is not necessary for growth -, 748086 4.1.1.11 physiological function the enzyme is involved in the regulation of pantothenate biosynthesis 747497 4.1.1.11 physiological function the MJ0050 gene complements the Escherichia coli panD deletion mutant cells, in which panD encoding aspartate decarboxylase in Escherichia coli has been knocked out, thus confirming the function of this gene in vivo -, 727784 4.1.1.11 physiological function the PanDZ complex regulates the pantothenate biosynthetic pathway in a cellular context in Escherichia coli by limiting the supply of beta-alanine in response to coenzyme A concentration. Formation of such a complex between activated aspartate decarboxylase (PanD) and regulatory protein PanZ leads to sequestration of the pyruvoyl cofactor as a ketone hydrate. Regulation of PanD is due to CoA-dependent interaction of PanZ and PanD 747128