Lipocalin / cytosolic fatty-acid binding protein family
Lipocalins are transporters for small hydrophobic molecules, such as lipids, steroid hormones, bilins, and retinoids. The family also encompasses the enzyme prostaglandin D synthase (EC:5.3.99.2). Alignment subsumes both the lipocalin and fatty acid ...
Lipocalins are transporters for small hydrophobic molecules, such as lipids, steroid hormones, bilins, and retinoids. The family also encompasses the enzyme prostaglandin D synthase (EC:5.3.99.2). Alignment subsumes both the lipocalin and fatty acid binding protein signatures from PROSITE. This is supported on structural and functional grounds. The structure is an eight-stranded beta barrel.
This domain is found in the alpha and beta chains of Complement component C8 (C8A/B), in Complement components C6 (C6) from humans, constituents of the membrane attack complex (MAC) that play a key role in the innate and adaptive immune response by f ...
This domain is found in the alpha and beta chains of Complement component C8 (C8A/B), in Complement components C6 (C6) from humans, constituents of the membrane attack complex (MAC) that play a key role in the innate and adaptive immune response by forming pores in the plasma membrane of target cells. This entry represents the rigid, disulfide-rich epidermal growth factor (EGF) domain, which is included in the regulatory segment of these proteins [1,2]. It is found C-terminal to the membrane attack complex perforin domain Pfam:PF01823 and N-terminal to the thrombospondin type 1 domain Pfam:PF00090.
The membrane-attack complex (MAC) of the complement system forms transmembrane channels. These channels disrupt the phospholipid bilayer of target cells, leading to cell lysis and death. A number of proteins participate in the assembly of the MAC. Fr ...
The membrane-attack complex (MAC) of the complement system forms transmembrane channels. These channels disrupt the phospholipid bilayer of target cells, leading to cell lysis and death. A number of proteins participate in the assembly of the MAC. Freshly activated C5b binds to C6 to form a C5b-6 complex, then to C7 forming the C5b-7 complex. The C5b-7 complex binds to C8, which is composed of three chains (alpha, beta, and gamma), thus forming the C5b-8 complex. C5b-8 subsequently binds to C9 and acts as a catalyst in the polymerisation of C9. Active MAC has a subunit composition of C5b-C6-C7-C8-C9{n}. Perforin is a protein found in cytolytic T-cell and killer cells. In the presence of calcium, perforin polymerises into transmembrane tubules and is capable of lysing, non-specifically, a variety of target cells. There are a number of regions of similarity in the sequences of complement components C6, C7, C8-alpha, C8-beta, C9 and perforin. The X-ray crystal structure of a MACPF domain reveals that it shares a common fold with bacterial cholesterol dependent cytolysins (Pfam:PF01289) such as perfringolysin O. Three key pieces of evidence suggests that MACPF domains and CDCs are homologous: Functional similarity (pore formation), conservation of three glycine residues at a hinge in both families and conservation of a complex core fold [1].
This domain is found in the alpha and beta chains of Complement component C8 (C8A/B), in Complement components C6 (C6) from humans, constituents of the membrane attack complex (MAC) that play a key role in the innate and adaptive immune response by f ...
This domain is found in the alpha and beta chains of Complement component C8 (C8A/B), in Complement components C6 (C6) from humans, constituents of the membrane attack complex (MAC) that play a key role in the innate and adaptive immune response by forming pores in the plasma membrane of target cells. This entry represents the rigid, disulfide-rich epidermal growth factor (EGF) domain, which is included in the regulatory segment of these proteins [1,2]. It is found C-terminal to the membrane attack complex perforin domain Pfam:PF01823 and N-terminal to the thrombospondin type 1 domain Pfam:PF00090.
The membrane-attack complex (MAC) of the complement system forms transmembrane channels. These channels disrupt the phospholipid bilayer of target cells, leading to cell lysis and death. A number of proteins participate in the assembly of the MAC. Fr ...
The membrane-attack complex (MAC) of the complement system forms transmembrane channels. These channels disrupt the phospholipid bilayer of target cells, leading to cell lysis and death. A number of proteins participate in the assembly of the MAC. Freshly activated C5b binds to C6 to form a C5b-6 complex, then to C7 forming the C5b-7 complex. The C5b-7 complex binds to C8, which is composed of three chains (alpha, beta, and gamma), thus forming the C5b-8 complex. C5b-8 subsequently binds to C9 and acts as a catalyst in the polymerisation of C9. Active MAC has a subunit composition of C5b-C6-C7-C8-C9{n}. Perforin is a protein found in cytolytic T-cell and killer cells. In the presence of calcium, perforin polymerises into transmembrane tubules and is capable of lysing, non-specifically, a variety of target cells. There are a number of regions of similarity in the sequences of complement components C6, C7, C8-alpha, C8-beta, C9 and perforin. The X-ray crystal structure of a MACPF domain reveals that it shares a common fold with bacterial cholesterol dependent cytolysins (Pfam:PF01289) such as perfringolysin O. Three key pieces of evidence suggests that MACPF domains and CDCs are homologous: Functional similarity (pore formation), conservation of three glycine residues at a hinge in both families and conservation of a complex core fold [1].
The membrane-attack complex (MAC) of the complement system forms transmembrane channels. These channels disrupt the phospholipid bilayer of target cells, leading to cell lysis and death. A number of proteins participate in the assembly of the MAC. Fr ...
The membrane-attack complex (MAC) of the complement system forms transmembrane channels. These channels disrupt the phospholipid bilayer of target cells, leading to cell lysis and death. A number of proteins participate in the assembly of the MAC. Freshly activated C5b binds to C6 to form a C5b-6 complex, then to C7 forming the C5b-7 complex. The C5b-7 complex binds to C8, which is composed of three chains (alpha, beta, and gamma), thus forming the C5b-8 complex. C5b-8 subsequently binds to C9 and acts as a catalyst in the polymerisation of C9. Active MAC has a subunit composition of C5b-C6-C7-C8-C9{n}. Perforin is a protein found in cytolytic T-cell and killer cells. In the presence of calcium, perforin polymerises into transmembrane tubules and is capable of lysing, non-specifically, a variety of target cells. There are a number of regions of similarity in the sequences of complement components C6, C7, C8-alpha, C8-beta, C9 and perforin. The X-ray crystal structure of a MACPF domain reveals that it shares a common fold with bacterial cholesterol dependent cytolysins (Pfam:PF01289) such as perfringolysin O. Three key pieces of evidence suggests that MACPF domains and CDCs are homologous: Functional similarity (pore formation), conservation of three glycine residues at a hinge in both families and conservation of a complex core fold [1].
This domain is found in the alpha and beta chains of Complement component C8 (C8A/B), in Complement components C6 (C6) from humans, constituents of the membrane attack complex (MAC) that play a key role in the innate and adaptive immune response by f ...
This domain is found in the alpha and beta chains of Complement component C8 (C8A/B), in Complement components C6 (C6) from humans, constituents of the membrane attack complex (MAC) that play a key role in the innate and adaptive immune response by forming pores in the plasma membrane of target cells. This entry represents the rigid, disulfide-rich epidermal growth factor (EGF) domain, which is included in the regulatory segment of these proteins [1,2]. It is found C-terminal to the membrane attack complex perforin domain Pfam:PF01823 and N-terminal to the thrombospondin type 1 domain Pfam:PF00090.
This is the MG2 (macroglobulin) domain of alpha-2-macroglobulin in eukaryotes [1]. 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. How ...
This is the MG2 (macroglobulin) domain of alpha-2-macroglobulin in eukaryotes [1]. 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. This domain is found in eukaryotic and bacterial proteins. In human A2Ms, this domain is termed macroglobulin-like (MG) domain 2 and in Salmonella enterica ser A2Ms, this is domain 4 [2] [3].
Complement component 5 (C5) is a component of the lytic complex consisting of factors C5-C9 which attack bacterial cell membranes. This entry represents the CUB domain [1-5].
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. This domain is found in eukaryotic and bacterial proteins. In human A2Ms, this domain encompasses macroglobulin-like domain MG5 and 6 including bait region. In Salmonella enterica ser A2Ms, this domain encompasses MG7 and MG8 including the bait region [1] [2]. The Bait region is cleaved by proteases, followed by a large conformational change that blocks the target protease within a cage-like complex. This model of protease entrapment is recognised as the Venus flytrap mechanism [1].
