The fourth arginine catabolic pathway of Pseudomonas aeruginosa.
The fourth arginine catabolic pathway of Pseudomonas aeruginosa.
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铜绿假单胞菌的第四种精氨酸分解代谢途径。
DOI：
10.1099/00221287-134-9-2633
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发表时间：
1988
期刊：
影响因子：
--
通讯作者：
D. Haas
中科院分区：
文献类型：
--
作者：
A. Jann;H. Matsumoto;D. Haas
在铜绿假单胞菌中发现了d -精氨酸脱氢酶活性。该酶可被底物d -精氨酸及其产物2-酮精氨酸诱导，但不能被l -精氨酸诱导。在人工电子受体（甲磺酸非那嗪和氯化碘硝基四唑）存在的情况下，测定了酶的体外活性。2-酮精氨酸进一步分解为4-胍丁醛、4-胍丁酸和4-氨基丁酸。2-酮精氨酸可诱导4-胍丁醛脱氢酶和胍丁醛丁酯酶；后一种酶也受到4-胍丁酸酯的强烈诱导。用体内法检测精氨酸消旋酶活性。e -精氨酸有可能通过d -精氨酸脱氢酶途径被分解，在外消旋化后，通过三种l -精氨酸分解代谢途径被分解，这些途径先前在铜绿假单胞菌中被证实。在l -精氨酸琥珀酰转移酶途径被阻断的突变体中，而在野生型中没有，l -精氨酸部分被引导到d-精氨酸脱氢酶途径中。kauB位点的突变使铜绿假单胞菌对2-酮精氨酸、agmatine和腐胺的生长受到抑制，并导致4-鸟嘌呤丁醛脱氢酶和4-氨基丁醛脱氢酶活性丧失。因此，这两种活性似乎是由铜绿假单胞菌中的一种酶引起的。kauB位点被定位在lysA和argB之间的染色体上，与已知的三种l -精氨酸分解代谢途径相关的基因无关。四种精氨酸分解代谢途径的存在说明了铜绿假单胞菌代谢的多功能性。
D-Arginine dehydrogenase activity was discovered in Pseudomonas aeruginosa. This enzyme was inducible by its substrate, D-arginine, as well as by its product, 2-ketoarginine, but not by L-arginine. The enzyme activity was measured in vitro, in the presence of artificial electron acceptore (phenazine methosulphate and iodonitrotetrazolium chloride). 2-ketoarginine was catabolized further to 4-guanidinobutyraldehyde, 4-guanidinobutyrate and 4-aminobutyrate. Two enzymes involved, 4-guanidinobutyraldehyde dehydrogenase and guanidinobutyrase, were inducible by 2-ketoarginine; the latter enzyme was also strongly induced by 4-guanidinobutyrate. An arginine racemase activity was detected by an invivo test. E-Arginine had the potential to be catabolized via the D-arginine dehydrogenase pathway and, after racemization, via the three L-arginine catabolic pathyways previously demonstrated in P. aeruginosa. In mutants blocked in the L-arginine succinyltransferase pathway, but no in the wild-type, L-arginine was channelled partially into the D-arginine dehydrogenase pathway. Mutations in the kauB locus abolished growth of P. aeruginosa on 2-ketoarginine, agmatine and putrescine, and led to loss of 4-guanidinobutyraldehyde dehydrogenase and 4-aminobutyaldehyde dehydrogenase activites. Thus, these two activites appear to be due to one enzyme in P. aeruginosa. The kauB locus was mapped on the chromosome between lysA and argB and was not linked to known genes involved in the three L-arginine catabolic pathways. The existence of four arginine catabolic pathways illustrates the metabolic versatility of P. aeruginosa.