| Title | A possible mechanism responsible for translocation and secretion an alkaliphilic bacillus sp. S-1 pullulanase |
|---|---|
| Author | Shim, Jae Kyoung · Kim, Kyoung Sook¹ · Kim, Cheorl Ho * |
| Address | Department of Biochemistry and Molecular Biology, College of Oriental Medicine, Dongguk University; ¹Molecular Glycobiology Research Unit, Korea Research Institute of Bioscience and Biotechnology |
| Bibliography | Journal of Microbiology, 35(3),213-221, 1997, |
| DOI | |
| Key Words | Alkaliphilic Bacillus sp. S-1, intracellular pullulanase, secretion, tranlocation |
| Abstract | The secretion of the alkaliphilic Bacillus sp. S-1 extracellular pullulanase involves translocation across the cytoplasmic membrane of the Gram-positive bacterial cell envelope. Translocation of the intracellular pullulanase PUL-I, was traced to elucidate the mechanism and pathway of protein secretion from an alkaliphilic Bacillus sp. S-1. Pullulanase could be slowly but quantitatively released into the medium during growth of the cells in medium containing proteinase K. The released pullulanase lacked the N-terminal domain. The N-terminus is the sole membrane anchor in the pullulanase protein and was not affected by proteases, confirming that it is not exposed on the cell surface. Processing of a 180,000M_r pullulanase to a 140,000M_r polypeptide has been demonstrated in cell extracts using antibodies raised against 140,000M_r extracellular form. Processing of the 180,000 M_r protein occured during the preparation of extracts in an alkaline pH condition. A modified rapid extraction procedure suggested that the processing event also occured in vivo. Processing apparently increased the activity of pullulanase. The western blotting analysis with mouse anti-serum against 140-kDa extracellular pullulanase PUL-E showed that PUL-I is processed into PUL-X via intermediate form of PUL-E. Possible explanationa for the translocation are discussed. |
| Download PDF | Eng_350310_213-221p.pdf |