Anderson K L, Blair B G
Department of Biological Sciences, Mississippi State University, Mississippi State 39762-5543, USA.
SAAS Bull Biochem Biotechnol. 1996;9:57-62.
Eubacterium cellulosolvens 5494 is a cellulolytic gram positive bacterium isolated from the rumen. Substrate specific regulation has not been previously demonstrated in any members of this genera. However, we have recently found that E. cellulosolvens regulates some of its membrane proteins. Growth on different substrates, including cellulose and cellobiose, gave different SDS-PAGE profiles of proteins from the membrane fraction. Using scanning electron microscopy, we also found that growth of E. cellulosolvens on cellulose induces an ultrastructural complex that is not present when grown on any other substrate. Further study revealed that this ultrastructure was subsequently lost when an alternative substrate was made available to cellulose growing cells. We also found that cellulose, cellobiose, and maltose utilization are inhibited in the presence of a glucose analog, indicating glucose is the preferred substrate.
解纤维真杆菌5494是从瘤胃中分离出的一种革兰氏阳性纤维素分解菌。此前在该属的任何成员中均未证明存在底物特异性调控。然而，我们最近发现解纤维真杆菌会调控其一些膜蛋白。在包括纤维素和纤维二糖在内的不同底物上生长时，膜组分中的蛋白质会呈现出不同的SDS-PAGE图谱。使用扫描电子显微镜，我们还发现解纤维真杆菌在纤维素上生长会诱导形成一种超微结构复合体，而在其他任何底物上生长时均不存在这种复合体。进一步研究表明，当向在纤维素上生长的细胞提供替代底物时，这种超微结构随后会消失。我们还发现，在存在葡萄糖类似物的情况下，纤维素、纤维二糖和麦芽糖的利用会受到抑制，这表明葡萄糖是首选底物。
