Vander Wauven C, Jann A, Haas D, Leisinger T, Stalon V
Institut de Recherches du C.E.R.I.A., Bruxelles, Belgium.
Arch Microbiol. 1988;150(4):400-4. doi: 10.1007/BF00408314.
Most Pseudomonas aeruginosa PAO mutants which were unable to utilize L-arginine as the sole carbon and nitrogen source (aru mutants) under aerobic conditions were also affected in L-ornithine utilization. These aru mutants were impaired in one or several enzymes involved in the conversion of N2-succinylornithine to glutamate and succinate, indicating that the latter steps of the arginine succinyltransferase pathway can be used for ornithine catabolism. Addition of aminooxyacetate, an inhibitor of the N2-succinylornithine 5-aminotransferase, to resting cells of P. aeruginosa in ornithine medium led to the accumulation of N2-succinylornithine. In crude extracts of P. aeruginosa an ornithine succinyltransferase (L-ornithine:succinyl-CoA N2-succinyltransferase) activity could be detected. An aru mutant having reduced arginine succinyltransferase activity also had correspondingly low levels of ornithine succinyltransferase. Thus, in P. aeruginosa, these two activities might be due to the same enzyme, which initiates aerobic arginine and ornithine catabolism.
大多数在有氧条件下无法利用L-精氨酸作为唯一碳源和氮源的铜绿假单胞菌PAO突变体（aru突变体）在L-鸟氨酸利用方面也受到影响。这些aru突变体中参与将N2-琥珀酰鸟氨酸转化为谷氨酸和琥珀酸的一种或几种酶存在缺陷，这表明精氨酸琥珀酰转移酶途径的后几步可用于鸟氨酸分解代谢。向鸟氨酸培养基中的铜绿假单胞菌静息细胞添加N2-琥珀酰鸟氨酸5-氨基转移酶抑制剂氨氧乙酸会导致N2-琥珀酰鸟氨酸积累。在铜绿假单胞菌的粗提物中可检测到鸟氨酸琥珀酰转移酶（L-鸟氨酸：琥珀酰辅酶A N2-琥珀酰转移酶）活性。精氨酸琥珀酰转移酶活性降低的aru突变体其鸟氨酸琥珀酰转移酶水平也相应较低。因此，在铜绿假单胞菌中，这两种活性可能归因于同一种酶，该酶启动有氧精氨酸和鸟氨酸分解代谢。
