Biomaterial Database

Sequence similarity between alpha 2-macroglobulin from the horseshoe crab, Limulus polyphemus, and proteins of the alpha 2-macroglobulin family from mammals. 1990

L Sottrup-Jensen, and W Borth, and M Hall, and J P Quigley, and P B Armstrong

Department of Molecular Biology, University of Aarhus, Denmark.

1. Purified alpha 2-macroglobulin (alpha 2M) from the American horseshoe crab, Limulus polyphemus was cleaved with trypsin and 20 of the tryptic peptides were sequenced and compared with the sequences of human alpha 2M, rat alpha 1M, alpha 2M, and alpha 1-inhibitor 3, and human complement proteins C3 and C4. 2. Ten of the peptides (233 residues), including that containing the thiol ester site, could be aligned unambiguously with stretches in mammalian alpha 2M, with a degree of identity greater than 30%. 3. The 12-residue thiol ester-containing peptide of Limulus alpha 2M showed 67% identity with the same stretch of human alpha 2M.

UI	MeSH Term	Description	Entries
D008969	Molecular Sequence Data	Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.	Sequence Data, Molecular,Molecular Sequencing Data,Data, Molecular Sequence,Data, Molecular Sequencing,Sequencing Data, Molecular
D008970	Molecular Weight	The sum of the weight of all the atoms in a molecule.	Molecular Weights,Weight, Molecular,Weights, Molecular
D010446	Peptide Fragments	Partial proteins formed by partial hydrolysis of complete proteins or generated through PROTEIN ENGINEERING techniques.	Peptide Fragment,Fragment, Peptide,Fragments, Peptide
D003176	Complement C3	A glycoprotein that is central in both the classical and the alternative pathway of COMPLEMENT ACTIVATION. C3 can be cleaved into COMPLEMENT C3A and COMPLEMENT C3B, spontaneously at low level or by C3 CONVERTASE at high level. The smaller fragment C3a is an ANAPHYLATOXIN and mediator of local inflammatory process. The larger fragment C3b binds with C3 convertase to form C5 convertase.	C3 Complement,C3 Precursor,Complement 3,Complement C3 Precursor,Complement Component 3,Precursor-Complement 3,Pro-C3,Pro-Complement 3,C3 Precursor, Complement,C3, Complement,Complement, C3,Component 3, Complement,Precursor Complement 3,Precursor, C3,Precursor, Complement C3,Pro C3,Pro Complement 3
D003181	Complement C4	A glycoprotein that is important in the activation of CLASSICAL COMPLEMENT PATHWAY. C4 is cleaved by the activated COMPLEMENT C1S into COMPLEMENT C4A and COMPLEMENT C4B.	C4 Complement,C4 Complement Component,Complement 4,Complement C4, Precursor,Complement Component 4,Pro-C4,Pro-complement 4,C4, Complement,Complement Component, C4,Complement, C4,Component 4, Complement,Component, C4 Complement,Pro C4,Pro complement 4
D006737	Horseshoe Crabs	An arthropod subclass (Xiphosura) comprising the North American (Limulus) and Asiatic (Tachypleus) genera of horseshoe crabs.	Crabs, Horseshoe,Limulus,Limulus polyphemus,Tachypleus,Xiphosura,Crab, Horseshoe,Horseshoe Crab,Xiphosuras
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000511	alpha-Macroglobulins	Glycoproteins with a molecular weight of approximately 620,000 to 680,000. Precipitation by electrophoresis is in the alpha region. They include alpha 1-macroglobulins and alpha 2-macroglobulins. These proteins exhibit trypsin-, chymotrypsin-, thrombin-, and plasmin-binding activity and function as hormonal transporters.	Slow alpha 2-Macroglobulins,alpha 2-Acute Phase Globulins,alpha-Macrofetoproteins,45S RNP,Acute-Phase alpha 1-Protein,Slow alpha 2-Globulin,alpha 1-Acute Phase Globulin,alpha 1-Acute Phase Protein,alpha 1-Macroglobulin,alpha 2-Acute Phase Globulin,alpha-Macrofetoprotein,Acute Phase alpha 1 Protein,RNP, 45S,Slow alpha 2 Globulin,Slow alpha 2 Macroglobulins,alpha 1 Acute Phase Globulin,alpha 1 Acute Phase Protein,alpha 1 Macroglobulin,alpha 1-Protein, Acute-Phase,alpha 2 Acute Phase Globulin,alpha 2 Acute Phase Globulins,alpha 2-Globulin, Slow,alpha 2-Macroglobulins, Slow,alpha Macrofetoprotein,alpha Macrofetoproteins,alpha Macroglobulins
D000595	Amino Acid Sequence	The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.	Protein Structure, Primary,Amino Acid Sequences,Sequence, Amino Acid,Sequences, Amino Acid,Primary Protein Structure,Primary Protein Structures,Protein Structures, Primary,Structure, Primary Protein,Structures, Primary Protein
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia