Berekaa M M, Steinbüchel A
Institut für Mikrobiologie, Westfälische Wilhelms-Universität Münster, D-48149 Münster, Germany.
Appl Environ Microbiol. 2000 Oct;66(10):4462-7. doi: 10.1128/AEM.66.10.4462-4467.2000.
Among several bacterial species belonging to the general Gordonia, Mycobacterium, Micromonospora, Pseudomonas, and Rhodococcus, only two mycobacterial isolates, Mycobacterium fortuitum strain NF4 and the new isolate Mycobacterium ratisbonense strain SD4, which was isolated from a sewage treatment plant, were capable of utilizing the multiply branched hydrocarbon squalane (2,6,10,15,19, 23-hexamethyltetracosane) and its analogous unsaturated hydrocarbon squalene as the sole carbon source for growth. Detailed degradation studies and high-pressure liquid chromatography analysis showed a clear decrease of the concentrations of squalane and squalene during biomass increase. These results were supported by resting-cell experiments using strain SD4 and squalane or squalene as the substrate. The degradation of acyclic isoprenoids and alkanes as well as of acids derived from these compounds was also investigated. Inhibition of squalane and squalene degradation by acrylic acid indicated the possible involvement of beta-oxidation in the degradation route. To our knowledge, this is the first report demonstrating the biodegradation of squalane by using defined axenic cultures.
在属于戈登氏菌属、分枝杆菌属、小单孢菌属、假单胞菌属和红球菌属的几种细菌中，只有两种分枝杆菌分离株，即偶然分枝杆菌NF4菌株和从污水处理厂分离出的新分离株拉蒂斯邦分枝杆菌SD4菌株，能够利用多支链烃角鲨烷（2,6,10,15,19,23 - 六甲基二十四烷）及其类似的不饱和烃角鲨烯作为唯一碳源进行生长。详细的降解研究和高压液相色谱分析表明，在生物量增加过程中，角鲨烷和角鲨烯的浓度明显降低。使用菌株SD4并以角鲨烷或角鲨烯作为底物的静息细胞实验支持了这些结果。还研究了无环类异戊二烯和烷烃以及这些化合物衍生的酸的降解情况。丙烯酸对角鲨烷和角鲨烯降解的抑制表明β - 氧化可能参与了降解途径。据我们所知，这是第一份使用确定的纯培养物证明角鲨烷生物降解的报告。
