Acyclic Terpene Utilization (Atu) in Pseudomonads

香茅醇和香叶醇等非环单萜类化合物是用于香料和食品工业的芳香化合物。这是令人惊讶的，因为一些报告表明，作为信号物质、杀虫剂和细胞毒性化合物(细胞凋亡诱导剂)的无环单萜具有很强的生物效应。香茅醇和相关甲基分支分子的代谢很难理解，最近关于香茅醇在铜绿假单胞菌中分解代谢的文献数据(Diaz-Perez等人)。[2004]AEM 70：5102)与我们实验室的发现相矛盾。本研究旨在揭示铜绿假单胞菌的两个基因簇(PA2011-PA2016和PA2886-PA2893)在香茅醇途径(上位途径)和亮氨酸降解途径(下位途径)中的作用，特别是关键酶(香叶酰-辅酶A羧基酶和甲基-巴豆酰-辅酶A羧基酶)和3-羟基-3-异己烯基-戊二酰辅酶A醋酸酯裂解酶的识别和分配。计划中的调查包括鉴定和分析香叶醇氧化中(至少一个)依赖钼的步骤，香叶醇氧化中的钼依赖步骤与香茅醇氧化惊人地不同。

Acyclic monoterpenes such as citronellol and geraniol are aroma compounds that are used in perfume and in food industry. This is astonishing because several reports indicate strong biological effects of acyclic monoterpenes as signalling substances, insecticides and cytotoxic compounds (apoptosis inducers). Metbolism of citronellol and related methyl-branched molecules is hardly understood and recent literature data on catabolism of citronellol in Pseudomonas aeruginosa (Diaz-Perez et al. [2004] AEM 70:5102) are in contradiction to findings in our lab. The aim of this proposal is to unravel the function of two gene clusters of P. aeruginosa (PA2011-PA2016 and PA2886-PA2893) with respect to the citronellol pathway (upper pathway) and to leucine degrading pathway (lower pathway); in particular, the respective key enzymes (geranyl-CoA carboylase and methyl-crotonyl-CoA carboxylase) and 3-hydroxy-3-isohexenyl-glutaryl CoA acetate lyase have to be identified and assigned to the corresponding genes. The planned investigations include identification and analysis of (at least one) molybdenum-dependent step in geraniol oxidation that is surprisingly different in citronellol oxidation.