Department of Laboratory Medicine, Chang Gung Memorial Hospital, Taoyuan, Taiwan.
Division of Infectious Diseases, Department of Internal Medicine, Chang Gung Memorial Hospital at Linkou, Chang Gung University College of Medicine, Taoyuan, Taiwan.
Front Cell Infect Microbiol. 2021 Nov 11;11:748640. doi: 10.3389/fcimb.2021.748640. eCollection 2021.
The von Willebrand factor binding protein in (vWbl) comprises four major regions: the signal peptide (S), the non-repetitive (A) region, the repeat (R) region, and the wall-associated (W) region. Previous studies have demonstrated that the R region contains 10 copies of repeating sequences; however, we reveal that the copy number of repeats in the gene varies among different isolates. In this study, an epidemiological surveillance was conducted to determine whether the copy number of repeats in in different isolates of correlates with their infectivity. The number of repeats was estimated in a total of 212 isolates, consisting of 162 isolates of oxacillin-sensitive (OSSL) and 50 isolates of oxacillin-resistant (ORSL). Our data showed that 72.5% (116/162) of OSSL isolates contained 9 (25, 15.4%), 12 (43, 26.5%), or 13 (48, 29.6%) repeats, and 90% (45/50) of ORSL isolates had 9 (32, 64%) or 13 (13, 26%) repeats. In addition, 89.6% (26 of 29) of the sequence type (ST)27 strain had 12 repeats, and 86.8% (13 of 15) of the ST4 strain had 14 repeats. Twenty-seven of the 28 isolates with nine repeats were of the staphylococcal cassette chromosome (SCC) V or V type and belonged to ST3, and all isolates with 13 repeats were of SCC II type and belonged to ST6. All isolates with nine repeats had a stop codon at the 18 codon of the third repeat, suggesting that these isolates coded for nonfunctional vWbl. Further, western blot analysis confirmed that all strains translated vWbl, and only vWbl proteins coded by genes with nine repeats were exported outside the cell. These results suggest that number of repeats in have clonal specificities and may correlate with potential pathogenicity.
血管性血友病因子结合蛋白（vWbl）由四个主要区域组成：信号肽（S）、非重复（A）区、重复（R）区和壁结合（W）区。先前的研究表明，R 区包含 10 个重复序列的拷贝；然而，我们揭示了不同 分离株中 基因的重复拷贝数存在差异。在这项研究中，进行了一项流行病学监测，以确定不同 分离株中 的重复拷贝数是否与其感染性相关。在总共 212 个分离株中，估计了重复次数，其中包括 162 个耐苯唑西林金黄色葡萄球菌（OSSL）分离株和 50 个耐苯唑西林金黄色葡萄球菌（ORSL）分离株。我们的数据显示，72.5%（116/162）的 OSSL 分离株含有 9（25，15.4%）、12（43，26.5%）或 13（48，29.6%）个重复，90%（45/50）的 ORSL 分离株含有 9（32，64%）或 13（13，26%）个重复。此外，89.6%（26/29）的 ST27 菌株有 12 个重复，86.8%（13/15）的 ST4 菌株有 14 个重复。28 个 9 个重复的分离株中有 27 个是葡萄球菌盒式染色体（SCC）V 或 V 型，属于 ST3，所有 13 个重复的分离株都是 SCC II 型，属于 ST6。所有 9 个重复的分离株在第三个重复的第 18 个密码子都有一个终止密码子，表明这些分离株编码的 vWbl 没有功能。此外，western blot 分析证实所有菌株都翻译了 vWbl，只有基因中 9 个重复的 vWbl 蛋白被输出到细胞外。这些结果表明， 中的重复次数具有克隆特异性，可能与潜在的致病性相关。
