黄色粘球菌发育阶段外膜蛋白表达的变化

【目的】黄色粘球菌是研究原核发育的一种模式生物，对其膜蛋白的研究仍然十分缺乏。【方法】利用6种预测软件，在黄色粘球菌的基因组中筛选编码外膜蛋白(OMP)的基因。根据报告基因lacZ，检测这些基因在营养性生长和发育阶段的表达。【结果】基于生物信息学分析，筛选出11个编码外膜蛋白的基因。其中2个基因(MXAN3106和MXAN3883)在发育阶段表达量上升,它们分别编码Secretin家族和Fimbrial usher protein (FUP)家族转运蛋白。其余9个基因在发育起始阶段表达量降低或保持较低水平，它们均编码TonB依赖型受体或外排蛋白。【结论】这些数据提示，黄色粘球菌由生长到发育的转换过程，伴随着膜蛋白表达的显著变化。

Changes in the expression of outer membrane proteins during Myxococcus xanthus development

Objective] The membrane proteins of Myxococcus xanthus, a model organism for studying prokaryotic development, remain an under-explored territory. Methods] Putative outer membrane protein (OMP)-encoding ORFs were selected from Myxococcus xanthus genome using six computational algorithms. With lacZ as a reporter, we monitored the expression profiles of these genes during vegetative growth and development. Results] Eleven putative OMPs have been identified based on bioinformatic analysis. Increased expression during development was found in two genes, MXAN3106 and MXAN3883, which were predicted to encode protein transporters of the secretin family and the fimbrial usher protein (FUP) family, respectively. The remaining nine genes that code for TonB-dependent receptors or efflux proteins exhibited a decreased expression or remained at a very low expression level after initiation of development. Conclusion] Our data suggest that for M. xanthus, switching from growth to development is associated with a dramatic change in the expression pattern of membrane proteins.