烃的选择性跨膜传输

研究了烃的跨膜传输过程以及该过程的选择性对细菌降解偏好性的影响。以乳化烷烃实施跨膜传输试验，发现在18h内细胞中的烃含量持续增加。对于各单组分烃，跨膜传输效率没有很大差异；但是，在混合烃的竞争性传输试验中，膜表现出显著的选择性。以分离度衡量膜对4种链长不等烷烃的选择性，发现十六烷，十七烷，二十烷和二十一烷的分离系数分别为1．468，1．121，0．886和0．466，该选择性次序与菌株1.766对混合烃的降解次序相符，说明烃的跨膜传输是决定菌株底物偏好性的重要因素。

Selective Transport of Alkanes into Cells of Alkane-degrading Bacteria

The process of alkanes transport into cells and the effect of transport selectivity on priority of different alkanes in hiodegradation were studied. An alkane transport experiment based on emulsion of alkanes shows that the inclusive alkanes in cells increase steadily in 18 hours during incubation with alkanes. The transport efficiency for each of the specific alkanes does not show remarkable difference, while for mixtures of alkanes, a signifi cant selectivity exists in the competitive transport experiment. The Selective factor of hexadecane, heptadecane, eicosane and heneicosane are 1. 468, 1. 121, 0. 886 and 0. 466, respectively, in which the order is consistent with the degradation order of each component degraded by P. marginata 1766. It suggests that the transport of alkanes into the cell is an important factor governing the priority of various alkanes in biodegradation.