Gliding Motility, Calcium, and Cohesion in Myxobacteria

钙离子对粘细菌有三种作用。它们是：(1)滑动运动系统的诱导；(2)能量依赖凝聚力系统的诱导；以及(3)三种特定多肽合成的刺激。长期的目标是提纯这些多肽，产生单抗，并使用这些抗体来验证这三种多肽在运动和/或凝聚力方面具有功能的假设。这些抗体将被用来克隆基因，为解决这个问题提供遗传途径，作为试图抑制运动性或凝聚力的直接试剂，并作为探针在其他滑行细菌中寻找交叉反应多肽。这笔赠款将支持启动对Stigmatella的遗传分析，生产单抗，并使用这些抗体亲和纯化蛋白质。粘细菌是具有分化能力的共生原核生物，其生命周期包括单细胞子实体阶段、聚集子实体阶段和多细胞子实体阶段。所有这些现象都没有在分子或机制层面上被理解。生物系统本身就很吸引人，很可能被证明是研究高等生物分化和细胞-细胞相互作用的有用模型系统。

Calcium ion has three effects on myxobacteria. These are: (1) the induction of a system for gliding motility; (2) the induction of a system for energy-dependent cohesion; and (3) the stimulation of synthesis of three specific polypeptides. The long-range goal is to purify these polypeptides, raise monoclonal antibodies, and use these antibodies to test the hypothesis that the three polypeptides are functionally involved in motility and/or cohesion. The antibodies will be used to clone the genes for genetic approaches to the question, as direct reagents to try to inhibit motility or cohesion, and as probes to search for crossreactive polypeptides in other gliding bacteria. The present grant will support initiation of genetic analysis in Stigmatella, production of monoclonal antibodies, and use of the antibodies to affinity purify the proteins. Myxobacteria are differentiation-competent, communal procaryotes, whose life-cycle includes single-celled, aggregating (cohesive), and multicellular fruiting body stages. None of these phenomena are understood at the molecular or mechanistic level. The biological system, fascinating in its own right, may well prove to be a useful model system for studying differentiation and cell-cell interactions in higher organisms.