gspM

gspM is a gene found in various bacterial species, notably in the *Escherichia coli* genome. It encodes a protein component of the type III secretion system (T3SS). The T3SS is a complex molecular machine that bacteria use to inject effector proteins directly into the cytoplasm of host cells. This injection process is crucial for many bacterial pathogenesis mechanisms, allowing bacteria to manipulate host cell functions, evade immune responses, or facilitate invasion.

The protein encoded by gspM is a component of the basal body of the T3SS, a structure embedded within the bacterial membranes that anchors the secretion needle and pore. Specifically, GspM is believed to be part of the ring structures that span the inner and outer membranes, providing structural support and facilitating the passage of secreted substrates. Its precise role within the basal body assembly and function is an area of ongoing research, but it is considered essential for the overall integrity and activity of the T3SS apparatus. Studies have shown that mutations in gspM can lead to defects in protein secretion, highlighting its importance in the T3SS machinery. The gene is often found as part of a larger gene cluster encoding all the necessary components for T3SS assembly and function.

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