Structures and functions of autotransporter proteins in microbial pathogens

Area of Science:

• Microbiology
• Molecular Biology
• Biochemistry

Background:

• Autotransporter proteins (AT) are the largest protein family in pathogenic Gram-negative bacteria.
• ATs possess a conserved structure with a translocator domain for outer membrane transport and a variable passenger domain for virulence functions.
• Recent findings challenge the 'auto' prefix, suggesting complex biogenesis pathways.

Purpose of the Study:

• To review recent advancements in understanding autotransporter protein biogenesis.
• To highlight key stages including protein transport, accessory protein involvement, and glycosylation.
• To discuss unresolved questions in autotransporter protein assembly and function.

Main Methods:

• Literature review of recent studies on autotransporter protein biogenesis.
• Analysis of structural and functional data related to AT domains and accessory proteins.
• Discussion of experimental evidence regarding protein translocation and post-translational modifications.

Main Results:

• Autotransporter biogenesis involves intricate steps beyond simple self-transport.
• Accessory proteins play significant roles in AT maturation and outer membrane translocation.
• Glycosylation of ATs is a notable post-translational modification in Gram-negative bacteria.

Conclusions:

• The biogenesis of autotransporter proteins is more complex than previously assumed.
• Further research is needed to fully elucidate the roles of accessory factors and the mechanisms of glycosylated AT translocation.
• Understanding AT biogenesis is critical for developing strategies against Gram-negative bacterial pathogens.