Alpha-2-macroglobulins (A2Ms) are plasma proteins that trap and inhibit a broad range of proteases and are major components of the eukaryotic innate immune system. However, A2M-like proteins were identified in pathogenically invasive bacteria and spe ...
Alpha-2-macroglobulins (A2Ms) are plasma proteins that trap and inhibit a broad range of proteases and are major components of the eukaryotic innate immune system. However, A2M-like proteins were identified in pathogenically invasive bacteria and species that colonize higher eukaryotes. Bacterial A2Ms are located in the periplasm where they are believed to provide protection to the cell by trapping external proteases through a covalent interaction with an activated thioester. This domain is found on the N-terminal region in A2Ms in bacteria. Structure analysis of Salmonella enterica ser A2Ms (SA-A2Ms) show that they are composed of 13 domains, all of which fold as variants of beta sandwiches with the exception of the TED, which consists of 14 alpha helices. Most of the beta sandwich domains appear to serve a structural role and are referred to as the macroglobulin-like (MG) domains. This is the MG1 domain which is the farthest from the body of the structure. It is normally anchored to the inner membrane in vivo and connected to MG2 by a flexible linker [1].
Bacterial alpha-2 macroglobulin (A2M) are located in the periplasm and may protect the cell by trapping external proteases through a covalent interaction with an activated thioester [1,2]. Macroglobulin (MG) beta sandwich domains appear to play a str ...
Bacterial alpha-2 macroglobulin (A2M) are located in the periplasm and may protect the cell by trapping external proteases through a covalent interaction with an activated thioester [1,2]. Macroglobulin (MG) beta sandwich domains appear to play a structural role. This entry represents bacterial MG2 (bMG2) domain which, with MG1, plays the role of a linker associating the main body of A2M to the bilayer [1-3].
