molecular function |
| GO:0005509 | | calcium ion binding | | Interacting selectively and non-covalently with calcium ions (Ca2+). |
| GO:0048306 | | calcium-dependent protein binding | | Interacting selectively and non-covalently with any protein or protein complex (a complex of two or more proteins that may include other nonprotein molecules), in the presence of calcium. |
| GO:0001855 | | complement component C4b binding | | Interacting selectively and non-covalently with the C4b product of the classical complement cascade. |
| GO:0016787 | | hydrolase activity | | Catalysis of the hydrolysis of various bonds, e.g. C-O, C-N, C-C, phosphoric anhydride bonds, etc. Hydrolase is the systematic name for any enzyme of EC class 3. |
| GO:0046872 | | metal ion binding | | Interacting selectively and non-covalently with any metal ion. |
| GO:0008233 | | peptidase activity | | Catalysis of the hydrolysis of a peptide bond. A peptide bond is a covalent bond formed when the carbon atom from the carboxyl group of one amino acid shares electrons with the nitrogen atom from the amino group of a second amino acid. |
| GO:0005515 | | protein binding | | Interacting selectively and non-covalently with any protein or protein complex (a complex of two or more proteins that may include other nonprotein molecules). |
| GO:0004252 | | serine-type endopeptidase activity | | Catalysis of the hydrolysis of internal, alpha-peptide bonds in a polypeptide chain by a catalytic mechanism that involves a catalytic triad consisting of a serine nucleophile that is activated by a proton relay involving an acidic residue (e.g. aspartate or glutamate) and a basic residue (usually histidine). |
| GO:0008236 | | serine-type peptidase activity | | Catalysis of the hydrolysis of peptide bonds in a polypeptide chain by a catalytic mechanism that involves a catalytic triad consisting of a serine nucleophile that is activated by a proton relay involving an acidic residue (e.g. aspartate or glutamate) and a basic residue (usually histidine). |
biological process |
| GO:0006956 | | complement activation | | Any process involved in the activation of any of the steps of the complement cascade, which allows for the direct killing of microbes, the disposal of immune complexes, and the regulation of other immune processes; the initial steps of complement activation involve one of three pathways, the classical pathway, the alternative pathway, and the lectin pathway, all of which lead to the terminal complement pathway. |
| GO:0006958 | | complement activation, classical pathway | | Any process involved in the activation of any of the steps of the classical pathway of the complement cascade which allows for the direct killing of microbes, the disposal of immune complexes, and the regulation of other immune processes. |
| GO:0001867 | | complement activation, lectin pathway | | Any process involved in the activation of any of the steps of the lectin pathway of the complement cascade which allows for the direct killing of microbes and the regulation of other immune processes. |
| GO:0002376 | | immune system process | | Any process involved in the development or functioning of the immune system, an organismal system for calibrated responses to potential internal or invasive threats. |
| GO:0045087 | | innate immune response | | Innate immune responses are defense responses mediated by germline encoded components that directly recognize components of potential pathogens. |
| GO:0006508 | | proteolysis | | The hydrolysis of proteins into smaller polypeptides and/or amino acids by cleavage of their peptide bonds. |
cellular component |
| GO:0070062 | | extracellular exosome | | A vesicle that is released into the extracellular region by fusion of the limiting endosomal membrane of a multivesicular body with the plasma membrane. Extracellular exosomes, also simply called exosomes, have a diameter of about 40-100 nm. |
| GO:0005576 | | extracellular region | | The space external to the outermost structure of a cell. For cells without external protective or external encapsulating structures this refers to space outside of the plasma membrane. This term covers the host cell environment outside an intracellular parasite. |