Periplasmic substrate-binding component of TRAP-type C4-dicarboxylate transport system DctP3 and DctP4; the type 2 periplasmic-binding protein fold
Goal: GMRP protocol and IGMP snooping protocol. Varnished transmission function of space-layer device. Will be used. Architectural Engi. IGMP version 3 adds support for “source filtering”. IGMP version 1 and version 2 allow hosts to join multicast groups but they don't check the source of the traffic.
This group includes uncharacterized DctP3 and DctP 4 subfamilies of TRAP Transporters specific to C4-dicarboxylates such as succinate, malate and fumarate. TRAP transporters are a large family of solute transporters ubiquitously found in bacteria and archaea. This CD also included some eukaryotic homologs that have not been functionally characterized. TRAP transporters are comprised of a periplasmic substrate-binding protein (SBP; often called the P subunit) and two unequally sized integral membrane components: a large transmembrane subunit involved in the translocation process (the M subunit) and a smaller membrane of unknown function (the Q subunit). The driving force of TRAP transporters is provided by electrochemical ion gradients (either protons or sodium ions) across the cytoplasmic membrane, rather than ATP hydrolysis. This substrate-binding domain belongs to the type 2 periplasmic binding fold protein superfamily (PBP2). The PBP2 proteins are typically comprised of two globular subdomains connected by a flexible hinge and bind their ligand in the cleft between these domains in a manner resembling a Venus flytrap.