Nanyang Technological University, Singapore, Republic of Singapore.
Biodegradation. 2010 Sep;21(5):825-32. doi: 10.1007/s10532-010-9347-y. Epub 2010 Mar 9.
Rubrivivax benzoatilyticus JA2 utilizes L: -tryptophan as the sole source of nitrogen for growth, and it has a doubling time of approximately 11 h (compared to 8 h with ammonium chloride). With cell free extracts in the presence of 2-oxoglutarate, indole-3-pyruvic acid, indole-3-acetaldehyde, indole-3-acetic acid, isatin, benzaldehyde, gallic acid and pyrogallol were identified using high performance liquid chromatography (HPLC) and liquid chromatography-mass spectroscopy (LC-MS) analysis. The conversion of L: -tryptophan into indole 3-pyruvic acid and glutamate by an enzyme aminotransferase was confirmed and the catabolism of indole-3-pyruvic acid via side chain oxidation followed by ring oxidation, gallic acid and pyrogallol were confirmed as metabolites. In addition, the proposed pathway sequential conversion of indole-3-pyruvic acid to the end product of pyrogallol was identified, including an enzymatic step that would convert isatin to benzaldehyde by an enzyme yet to be identified. At this stage of the study, the enzyme tryptophan aminotransferase in R. benzoatilyticus JA2 was demonstrated.
黄壤红球菌 JA2 利用 L: -色氨酸作为唯一氮源进行生长,其倍增时间约为 11 小时(与使用氯化铵时的 8 小时相比)。使用 2-氧代戊二酸、吲哚-3-丙酮酸、吲哚-3-乙醛、吲哚-3-乙酸、靛蓝、苯甲醛、没食子酸和焦儿茶酚的无细胞提取物,通过高效液相色谱 (HPLC) 和液相色谱-质谱 (LC-MS) 分析进行鉴定。通过氨基转移酶将 L: -色氨酸转化为吲哚-3-丙酮酸和谷氨酸的反应得到确认,吲哚-3-丙酮酸通过侧链氧化和环氧化转化为没食子酸和焦儿茶酚的代谢途径得到确认。此外,还确定了吲哚-3-丙酮酸到最终产物焦儿茶酚的提议途径顺序转化,包括一个酶促步骤,该步骤将通过尚未鉴定的酶将靛蓝转化为苯甲醛。在研究的这个阶段,证明了黄壤红球菌 JA2 中的色氨酸氨基转移酶。