|
ツゲ ヒデアキ
TSUGE HIDEAKI
津下 英明 所属 京都産業大学 生命科学部 先端生命科学科 職種 教授 |
|
| 言語種別 | 英語 |
| 発行・発表の年月 | 2012 |
| 形態種別 | 研究論文 |
| 査読 | 査読あり |
| 標題 | Role of side-edge site of sphingomyelinase from Bacillus cereus |
| 執筆形態 | その他 |
| 掲載誌名 | Biochemical and Biophysical Research Communications |
| 出版社・発行元 | ACADEMIC PRESS INC ELSEVIER SCIENCE |
| 巻・号・頁 | 422(1),pp.128-132 |
| 著者・共著者 | Oda, M.,Takahashi, M.,Tsuge, H.,Nagahama, M.,Sakurai, J. |
| 概要 | Bacillus cereus sphingomyelinase (Bc-SMase) belongs to the Mg2+-dependent neutral sphingomyelinase (nSMase) which hydrolyzes sphingomyelin (SM) to produce phosphocholine and ceramide, and acts as an extracellular hemolysin. Bc-SMase has two metal ion-binding sites in a long horizontal cleft across the molecule, with one Mg2+ in the central region of the cleft and one divalent metal ion at the side-edge of the cleft. The role of the Mg2+ at the side-edge of the long horizontal cleft in Bc-SMase remains unresolved. The replacement of Asn-57, Glu-99, and Asp-100 located in close proximity to Mg2+ at the side-edge with alanine resulted in a striking reduction in binding to and hydrolysis of sphingomyelin in membranes of sheep erythrocytes or SM-liposomes but that of Phe-55 did not. However, the replacement of these residues had little effect on the enzymatic activity. N57A, E99A, and D100A contained 2 mol of Mg2+. per mol of protein, and the wild type and F55A contained 3 mol. A crystal analysis showed that N57A with Mg2+ had no metal ion at the side-edge. These results indicate that the Mg2+ at the side-edge of Bc-SMase plays an important role in the binding to membranes. Published by Elsevier Inc. |
| DOI | 10.1016/j.bbrc.2012.04.120 |
| ISSN | 0006-291X |
| Put Code(ORCID) | 6110959 |
| PermalinkURL | http://www.scopus.com/inward/record.url?eid=2-s2.0-84861458557&partnerID=MN8TOARS |