TY - JOUR
T1 - Methanococcus jannaschii uses a pyruvoyl-dependent arginine decarboxylase in polyamine biosynthesis
AU - Graham, David E.
AU - Xu, Huimin
AU - White, Robert H.
PY - 2002/6/28
Y1 - 2002/6/28
N2 - The genome sequence of the hyperthermophilic methanogen Methanococcus jannaschii contains homologs of most genes required for spermidine polyamine biosynthesis. Yet genomes from neither this organism nor any other euryarchaeon have orthologs of the pyridoxal 5′-phosphate-dependent ornithine or arginine decarboxylase genes, required to produce putrescine. Instead, as shown here, these organisms have a new class of arginine decarboxylase (PvlArgDC) formed by the self-cleavage of a proenzyme into a 5-kDa subunit and a 12-kDa subunit that contains a reactive pyruvoyl group. Although this extremely thermostable enzyme has no significant sequence similarity to previously characterized proteins, conserved active site residues are similar to those of the pyruvoyl-dependent histidine decarboxylase enzyme, and its subunits form a similar (αβ)3 complex. Homologs of PvlArgDC are found in several bacterial genomes, including those of Chlamydia spp., which have no agmatine ureohydrolase enzyme to convert agmatine (decarboxylated arginine) into putrescine. In these intracellular pathogens, PvlArgDC may function analogously to pyruvoyl-dependent histidine decarboxylase; the cells are proposed to import arginine and export agmatine, increasing the pH and affecting the host cell's metabolism. Phylogenetic analysis of Pvl-ArgDC proteins suggests that this gene has been recruited from the euryarchaeal polyamine biosynthetic pathway to function as a degradative enzyme in bacteria.
AB - The genome sequence of the hyperthermophilic methanogen Methanococcus jannaschii contains homologs of most genes required for spermidine polyamine biosynthesis. Yet genomes from neither this organism nor any other euryarchaeon have orthologs of the pyridoxal 5′-phosphate-dependent ornithine or arginine decarboxylase genes, required to produce putrescine. Instead, as shown here, these organisms have a new class of arginine decarboxylase (PvlArgDC) formed by the self-cleavage of a proenzyme into a 5-kDa subunit and a 12-kDa subunit that contains a reactive pyruvoyl group. Although this extremely thermostable enzyme has no significant sequence similarity to previously characterized proteins, conserved active site residues are similar to those of the pyruvoyl-dependent histidine decarboxylase enzyme, and its subunits form a similar (αβ)3 complex. Homologs of PvlArgDC are found in several bacterial genomes, including those of Chlamydia spp., which have no agmatine ureohydrolase enzyme to convert agmatine (decarboxylated arginine) into putrescine. In these intracellular pathogens, PvlArgDC may function analogously to pyruvoyl-dependent histidine decarboxylase; the cells are proposed to import arginine and export agmatine, increasing the pH and affecting the host cell's metabolism. Phylogenetic analysis of Pvl-ArgDC proteins suggests that this gene has been recruited from the euryarchaeal polyamine biosynthetic pathway to function as a degradative enzyme in bacteria.
UR - http://www.scopus.com/inward/record.url?scp=0037189491&partnerID=8YFLogxK
U2 - 10.1074/jbc.M203467200
DO - 10.1074/jbc.M203467200
M3 - Article
C2 - 11980912
AN - SCOPUS:0037189491
SN - 0021-9258
VL - 277
SP - 23500
EP - 23507
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 26
ER -