MOLECULAR MECHANISM OF VIRULENT FACTOR PRODUCTION IN GRAM POSITIVE BACTERIA

研究革兰氏阳性菌产生毒素和其他毒力因子的分子机制，为革兰氏阳性菌产生多种致人疾病的毒力因子制定新的感染控制措施。毒素和酶的产生受环境因素的调控。产气荚膜梭菌中α、β、γ、ε、θ等毒素的产生，艰难梭菌中毒素A和毒素B的产生，金黄色葡萄球菌中可溶性和表面毒力因子的产生受生长阶段、细菌密度/种群（群体感应）、碳源和营养底物、细胞间因子（如费洛蒙）的调节。在压力条件下的细菌，即；高温、极端pH值、重金属、抗生素的存在，使细菌诱发了应激相关基因，包括毒性基因。感知环境因素的特定受体。每种细菌对环境因素都有特定的受体，例如……，最常见的是双组份系统的传感器组件。在产气荚膜荚膜荚膜菌中，已经鉴定出几个系统，其中一个系统用于激活，另一个系统用于抑制毒素的产生。在金黄色葡萄球菌中，主要鉴定出锌、碱性、β-内酰胺类受体。细菌中的信息传递网络。随着产气荚膜荚膜杆菌和葡萄球菌的基因组分析，从受体到效应器产生的细菌信息传递系统的分子基础已经被明确，这是一个具有全球调控系统的序列“分子网络”。这些信息对今后抗生素的设计有一定的参考价值。细胞转录、翻译、翻译后和分泌水平的调控。在这些结果的基础上，毒性因子产生的分子网络得到了更明确的确认，这将有助于那些正在寻找更有效的抗感染药物和预防措施的人。少

Molecular mechanism of production of toxins and the other virulence factors in Gram positive bacteria has been investigated to develop novel infection control measures for Gram positive bacteria which produce variety of virulence factors to cause desease in human.1. The production of toxins and enzymes was regulated by the environmental factors.The production of toxins (α, β, γ, ε, θ, etc, in Clostridium perfringens, toxin A and B in C. difficile, soluble and surface virulent factors in Staphylococcus aureus) was regulated by the growth phase, density/population of bacteria (quoram sensing), carbon source and nutritional substrate, inter-cellular factors (like pheromon). Under the stressful condition for bacteria, ie ; heat, extream pH, in the presence of heavy metals, antibiotics, the bacteria induced the stress responsible genes including virulent genes.2. Specific receptors for sensing environmental factors.Each bacterium has a certain specific receptors for environmental factors, i … More .e., the most common one is the sensor component of two-component system. In C. perfringens, several systems have been identified, among which one for activation and the other for inhibition of production of toxin. In S. aureus, the receptors for zinc, alkaline, β-lactams were mostly identified.3. Information transmitting network in bacteria.Along with genomic analysis of C. perfringens, and that of Staphylococci, molecular basis of information transmitting system in bacteria has been made clear from receptor to effecter production as an sequential "molecular net work" with global regulatory system. This information is useful for the design of antibiotics in future.4. Regulation at the level of transcription, translation, post translation and secretion from cell.On basing upon those results, molecular net work of virulent factor production has been more clearly confirmed and the results will contribute to those who are looking for more specific effective anti-infection drugs and preventive measures. Less