PROTEIN PHOSPHORYLATION IN MYCOPLASMA PNEUMONIAE

肺炎支原体属于无细胞壁肺炎支原体 原核生物柔膜菌，其中包括最小和最简单的免费- 人类已知的活细菌。支原体具有有限的生物合成 能力，许多物种采取了寄生的生活方式。 因此，支原体对公共卫生和人类健康都有很大的影响。 和农业 M.肺炎是人类呼吸道疾病的病原体， 道和肺炎的主要原因，在较大的儿童和青年 成年人了 坚持M。pneumoniae对宿主细胞的粘附（cytadherence）是 成功殖民和疾病的关键 支原体蛋白HMW 1 是一种相位可变的膜蛋白， 在细胞粘附中的作用。 HMW 1表现出不寻常的亚细胞分布， 与丝状细胞延伸特异性相关， 主要但不排他地与细胞分裂素样 triton shell of M.肺炎。 该建议扩展了初步数据，表明HMW 1是 磷酸化。 该项目涉及以下基本问题： 体外和体内磷酸化的表征，以及 HMW 1中磷酸化残基的鉴定和定位。 将采用标准技术来评估32 P掺入到 HMW 1在培养和体外。 将对HMW 1进行生化分析 以鉴定磷酸化残基并将这些残基定位于 一级氨基酸序列。 最后，HMW 1的磷酸化 将检查与其分区特性的相关性 在Triton X-100和支原体细胞粘附中。 模型系统 提供了许多有吸引力的特征，包括靶蛋白， 与可识别功能（细胞粘附）相关，以及 缺乏HMW 1的变体的可用性，HMW 1的特异性抗体的可用性， 和推导的氨基酸序列，这是目前来自 HMW 1的克隆基因。 从这些研究中获得的信息将 为实现确定一个长期目标提供必要的基础 HMW 1磷酸化对蛋白质功能的重要性。

Mycoplasma pneumoniae is a member of the class of cell wall-less prokaryotes Mollicutes, which includes the smallest and simplest free- living bacteria known to man. Mycoplasmas have limited biosynthetic capabilities, and many species have resorted to a parasitic lifestyle. As a consequence, mycoplasmas have a great impact on both public health and agriculture. M. pneumoniae is a pathogen of the human respiratory tract and the leading cause of pneumonia in older children and young adults. Adherence by M. pneumoniae to host cells (cytadherence) is pivotal to successful colonization and disease. Mycoplasma protein HMW1 is a phase-variable membrane protein that appears to have an accessory role in cytadherence. HMW1 exhibits an unusual subcellular distribution, being associated specifically with filamentous cell extensions and partitioning primarily, but not exclusively, with the cytoskeleton-like triton shell of M. pneumoniae. This proposal expands upon preliminary data which indicate that HMW1 is phosphorylated. The project addresses fundamental questions regarding the characterization of phosphorylation in vitro and in vivo, as well as the identification and localization of phosphorylated residues in HMW1. Standard techniques will be employed to assess incorporation of 32P into HMW1 during culture and in vitro. HMW1 will be analyzed biochemically to identify phosphorylated residues and localize those residues within the primary amino acid sequence. Finally, the phosphorylation of HMW1 will be examined for a correlation with its partitioning characteristics in Triton X-100 and with mycoplasma cytadherence. The model system offers a number of attractive features, including a target protein associated with an identifiable function (cytadherence), as well as the availability of variants lacking HMW1, of specific antibodies to HMW1, and of deduced amino acid sequence, that is currently being derived from the cloned gene for HMW1. The information gained from these studies will provide the necessary foundation for the long-term objective of defining the significance of HMW1 phosphorylation to protein function.