Reichlin F, Kohler H P
Swiss Federal Institute for Environmental Sciences and Technology (EAWAG), Dübendorf.
Appl Environ Microbiol. 1994 Dec;60(12):4587-91. doi: 10.1128/aem.60.12.4587-4591.1994.
Pseudomonas sp. strain HBP1 Prp grew on 2-isopropylphenol as the sole carbon and energy source with a maximal specific growth rate of 0.14 h-1 and transient accumulation of isobutyric acid. Oxygen uptake experiments with resting cells and enzyme assays with crude-cell extracts showed that 2-isopropylphenol was catabolized via a broad-spectrum meta cleavage pathway. These findings were confirmed by experiments with partially purified enzymes. Identification of 3-isopropylcatechol and 2-hydroxy-6-oxo-7-methylocta-2,4-dienoic acid as the products of the initial monooxygenase reaction and the subsequent extradiol ring cleavage dioxygenase reaction, respectively, was based on gas chromatography-mass spectrometry analysis of the corresponding trimethylsilyl derivatives. The meta cleavage product hydrolase hydrolyzed 2-hydroxy-6-oxo-7-methylocta-2,4-dienoic acid (meta cleavage product of 2-isopropylphenol) to isobutyric acid and 2-hydroxypent-2,4-dienoic acid.
假单胞菌属菌株HBP1 Prp能以2-异丙基苯酚作为唯一碳源和能源生长,最大比生长速率为0.14 h-1 ,并短暂积累异丁酸。对静息细胞进行的氧摄取实验以及对粗细胞提取物进行的酶活性测定表明,2-异丙基苯酚通过广谱间位裂解途径进行分解代谢。这些发现通过部分纯化酶的实验得到了证实。通过对相应三甲基硅烷基衍生物的气相色谱-质谱分析,分别鉴定出3-异丙基邻苯二酚和2-羟基-6-氧代-7-甲基辛-2,4-二烯酸为初始单加氧酶反应和随后的双加氧酶间位环裂解反应的产物。间位裂解产物水解酶将2-羟基-6-氧代-7-甲基辛-2,4-二烯酸(2-异丙基苯酚的间位裂解产物)水解为异丁酸和2-羟基戊-2,4-二烯酸。