Bayer E A, Lamed R
J Bacteriol. 1986 Sep;167(3):828-36. doi: 10.1128/jb.167.3.828-836.1986.
The ultrastructural distribution of the cellulosome (a cellulose-binding, multicellulase-containing protein complex) on the cell surface of Clostridium thermocellum YS was examined by cytochemical techniques and immunoelectron microscopy. When cells of the bacterium were grown on cellobiose, cellulosome complexes were compacted into quiescent exocellular protuberant structures. However, when the same cells were grown on cellulose, these polycellulosomal organelles underwent extensive structural transformation; after attachment to the insoluble substrate, the protuberances protracted rapidly to form fibrous "contact corridors." The contact zones mediated physically between the cellulosome (which was intimately attached to the cellulose matrix) and the bacterial cell surface (which was otherwise detached from its substrate). In addition, cell-free cellulosome clusters coated the surface of the cellulose substrate. The cellulose-bound cellulosome clusters appear to be the site of active cellulolysis, the products of which are conveyed subsequently to the cell surface via the exocellular contact zones.
通过细胞化学技术和免疫电子显微镜检查了热纤梭菌YS细胞表面的纤维小体（一种纤维素结合、含多种纤维素酶的蛋白质复合物）的超微结构分布。当该细菌细胞在纤维二糖上生长时，纤维小体复合物被压缩成静止的细胞外突出结构。然而，当相同的细胞在纤维素上生长时，这些多纤维小体细胞器会发生广泛的结构转变；附着在不溶性底物上后，突出物迅速伸长形成纤维状的“接触通道”。接触区在纤维小体（紧密附着于纤维素基质）和细菌细胞表面（否则与底物分离）之间进行物理介导。此外，无细胞的纤维小体簇覆盖在纤维素底物表面。与纤维素结合的纤维小体簇似乎是活跃纤维素分解的场所，其产物随后通过细胞外接触区输送到细胞表面。
