Biomaterial Database

The quaternary structure of wheat-germ aspartate transcarbamoylase. 1982

R J Yon, and J E Grayson, and A Chawda, and P J Butterworth

1. The molecular mass of aspartate transcarbamoylase purified from wheat germ was found to be 101kDa by sucrose-density-gradient centrifugation, 103kDa by gel-filtration chromatography and 108kDa by polyacrylamide-gel electrophoresis. A mean value of 104 +/- 11kDa was obtained by pooling several replicate results from each method. 2. Polyacrylamide-gel electrophoresis in the presence of sodium dodecyl sulphate indicated a single size of polypeptide chain of mean molecular mass 37 +/- 4kDa. The ratio of the mean molecular masses of the active and denatured enzymes is 2.8.3. When the active enzyme was covalently cross-linked at a low protein concentration by dimethyl suberimidate, and then examined electrophoretically under denaturing conditions, three size species were observed to predominate, of apparent molecular masses 36, 77 and 106kDa respectively. 4. These results indicate that the intact, fully regulatory enzyme is a simple trimer, slightly larger than the trimeric "catalytic subunit' of the aspartate transcarbamoylase from Escherichia coli [Weber (1968) Nature (London) 218, 1116-1118]. The prevalence of trimeric structures amongst carbamoyl-transferase enzymes is discussed.

UI	MeSH Term	Description	Entries
D008970	Molecular Weight	The sum of the weight of all the atoms in a molecule.	Molecular Weights,Weight, Molecular,Weights, Molecular
D004120	Dimethyl Suberimidate	The methyl imidoester of suberic acid used to produce cross links in proteins. Each end of the imidoester will react with an amino group in the protein molecule to form an amidine.	Bismethyl Suberimidate,Dimethylsuberimidate,Suberimidate, Bismethyl,Suberimidate, Dimethyl
D004591	Electrophoresis, Polyacrylamide Gel	Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.	Polyacrylamide Gel Electrophoresis,SDS-PAGE,Sodium Dodecyl Sulfate-PAGE,Gel Electrophoresis, Polyacrylamide,SDS PAGE,Sodium Dodecyl Sulfate PAGE,Sodium Dodecyl Sulfate-PAGEs
D001221	Aspartate Carbamoyltransferase	An enzyme that catalyzes the conversion of carbamoyl phosphate and L-aspartate to yield orthophosphate and N-carbamoyl-L-aspartate. (From Enzyme Nomenclature, 1992) EC 2.1.3.2.	Aspartate Transcarbamylase,Co(II)-Aspartate Transcarbamoylase,Ni(II)-Aspartate Transcarbamoylase,Carbamoyltransferase, Aspartate,Transcarbamylase, Aspartate
D012639	Seeds	The encapsulated embryos of flowering plants. They are used as is or for animal feed because of the high content of concentrated nutrients like starches, proteins, and fats. Rapeseed, cottonseed, and sunflower seed are also produced for the oils (fats) they yield.	Diaspores,Elaiosomes,Embryos, Plant,Plant Embryos,Plant Zygotes,Zygotes, Plant,Diaspore,Elaiosome,Embryo, Plant,Plant Embryo,Plant Zygote,Seed,Zygote, Plant
D014908	Triticum	A plant genus of the family POACEAE that is the source of EDIBLE GRAIN. A hybrid with rye (SECALE CEREALE) is called TRITICALE. The seed is ground into FLOUR and used to make BREAD, and is the source of WHEAT GERM AGGLUTININS.	Wheat,Durum Wheat,Triticum aestivum,Triticum durum,Triticum spelta,Triticum turgidum,Triticum turgidum subsp. durum,Triticum vulgare,Durum Wheats,Wheat, Durum
D046911	Macromolecular Substances	Compounds and molecular complexes that consist of very large numbers of atoms and are generally over 500 kDa in size. In biological systems macromolecular substances usually can be visualized using ELECTRON MICROSCOPY and are distinguished from ORGANELLES by the lack of a membrane structure.	Macromolecular Complexes,Macromolecular Compounds,Macromolecular Compounds and Complexes,Complexes, Macromolecular,Compounds, Macromolecular,Substances, Macromolecular