Identification and isolation of three proteasome subunits and their encoding genes from Trypanosoma brucei.
Molecular Biochemistry and Parasitology
211 - 223.
We have determined peptide sequences of three Trypanosoma brucei proteasome subunit proteins by mass spectrometry of tryptic digests of the proteins purified by two-dimensional (2-D) polyacrylamide gel electrophoresis. Three genes identified by the sequence of their cDNA encode the peptides identified in these three proteins. The three proteins predicted from the gene sequences have significant similarity to other known proteasome subunits and represent an alpha6 type subunit (TbPSA6), and two beta-type subunits belonging to the beta1-type (TbPSB1) and beta2 type (TbPSB2). The sequences of both beta-subunits predict formation of catalytically active subunits through proteolytic processing. The prediction is supported by the presence in each of the two beta-subunits of a tryptic peptide that has the correctly processed N-terminus that creates the threonine nucleophile of the mature protein. This peptide cannot be generated by trypsin because of the required cleavage of a glycine-threonine bond. It is thus likely that there are at least two catalytically active beta-subunits, TbPSB1 and TbPSB2, present in the mature 20S proteasome from T. brucei
|Title:||Identification and isolation of three proteasome subunits and their encoding genes from Trypanosoma brucei|
|Additional information:||UI - 99426466 LA - Eng RN - EC 3.4.22 (Cysteine Endopeptidases) RN - EC 188.8.131.52 (multicatalytic endopeptidase complex) RN - 0 (DNA, Complementary) RN - 0 (Multienzyme Complexes) PT - JOURNAL ARTICLE ID - AI-21786/AI/NIAID DA - 19991209 IS - 0166-6851 SB -M CY - NETHERLANDS JC - NOR AA - Author EM - 200002|
|Keywords:||Genes, DNA, Id, Amino Acid Sequence, Animal, California, cDNA, chemistry, Cloning, Molecular, Cysteine, Cysteine Endopeptidases, DNA, Complementary, Electrophoresis, Gel, Two-Dimensional, enzymology, GENE, Genes, Protozoan, genetics, isolation & purification, metabolism, Methods, Molecular Sequence Data, Multienzyme Complexes, peptides, Proteins, Sequence Analysis, DNA, Spectrum Analysis, Mass, Support, Non-U.S.Gov't, Support, U.S.Gov't, P.H.S., Threonine, Trypanosoma brucei brucei, Trypsin, ANS, predictions|
|UCL classification:||UCL > School of Life and Medical Sciences > Faculty of Life Sciences > Biosciences (Division of)|
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