Semi-preparative HPLC purification of ribosomal proteins from Bacillus stearothermophilus and sequence determination of the highly conserved protein S19

Isolation and amino acid sequence of the 30S ribosomal protein S19 from Mycobacterium bovis BCG

The 30S ribosomal proteins from Mycobacterium bovis BCG were separated by reverse phase-high performance liquid chromatography (RP-HPLC). The isolated proteins were analyzed by SDS-PAGE, blotted on PVDF-membranes and subjected to sequence analyses using a gas-phase sequencer to correlate them to those of the well studied Escherichia coli and Bacillus stearothermophilus ribosomes. Moreover, the internal amino acid sequence of one ribosomal protein, MboS19, which is homologous to E. coli ribosomal protein S19 (EcoS19) and B. stearothermophilus ribosomal protein S19 (BstS19), was further analyzed by sequencing its internal peptides and two segments from the N- and C-termini of the protein were selected to deduce the sequence of two oligonucleotide primers which were used in a polymerase chain reaction. Using the amplified DNA fragment thus obtained as a hybridization probe, the gene encoding protein S19 was identified and cloned. Sequence analysis of the DNA fragment, together with peptide sequence analysis could determine the complete amino acid sequence of MboS19. This sequence proved to be 64% and 71% identical to those of the corresponding S19 proteins from the eubacteria E. coli, and B. stearothermophilus, respectively; 33% of the residues of MboS19 were identical to those in the archaebacterial ribosomal protein HmaS19.

rig encodes ribosomal protein S15. The primary structure of mammalian ribosomal protein S15

rig, a gene originally isolated from a rat insulinoma cDNA library, codes for a basic 145 amino acid protein [( 1986) Diabetes 35, 1178-1180]. Here we show that the immunoreactivity to a monoclonal antibody against the deduced rig protein and the translation product of rig mRNA comigrated with ribosomal protein S15. The amino acid sequence of ribosomal protein S15 purified from rat liver coincided with that deduced from the nucleotide sequence of rig mRNA, but there were indications that the initiator methionine was removed and the succeeding alanyl residue was monoacetylated. From these results, we conclude that the product of rig is ribosomal protein S15.

Applications of preparative high-performance liquid chromatography to the separation and purification of peptides and proteins

The basic differences between the problems encountered in the development of the analytical and preparative applications of high-performance liquid chromatography are analyzed and the principles of optimization of a preparative separation outlined. The application of these principles to the purification of peptides and proteins are discussed with emphasis on the specific problems raised by the separation of high-molecular-mass compounds. The relative advantages and inconveniences of displacement and overloaded elution are presented. The applications of the various retention modes of liquid chromatography (ion exchange, reversed-phase adsorption, hydrophobic interactions, size exclusion and bioaffinity) to the separation of various peptide and protein mixtures and/or to the extraction and purification of some of these compounds are reviewed. Separation performance reported in the literature are summarized in table form.

The complete amino acid sequence of ribosomal protein S18 from the moderate thermophile Bacillus stearothermophilus

The amino acid sequence of ribosomal protein S18 from Bacillus stearothermophilus has been completely determined by automated sequence analysis of the intact protein as well as of peptides derived from digestion with Staphylococcus aureus protease at pH 4.0 and cleavage with cyanogen bromide. The carboxy-terminal region was verified by both amino acid analyses of chymotryptic peptides and by mass spectrometry from the terminal region. The protein contains 77 amino acid residues and has an Mr of 8838. Comparison of this sequence with the sequences of the S18 proteins from tobacco and liverwort chloroplasts and E. coli shows a relatively high similarity, ranging from 42 to 55% identical residues with the B. stearothermophilus S18 protein. The regions of homology common to all four proteins consist of several positively charged sections spanning the entire length of the protein.

Cross-linked amino acids in the protein pair S13-S19 and sequence analysis of protein S13 of Bacillus stearothermophilus ribosomes

The 30S ribosomal subunits from Bacillus stearothermophilus were cross-linked under native conditions with the bifunctional reagent diepoxybutane. The dominant protein-protein cross-link in the 30S ribosomal subunit between proteins S13 and S19 [Brockmöller, J., & Kamp, R.M. (1986) Biol. Chem. Hoppe-Seyler 367, 925-935] was isolated on a preparative scale. The presence of a single cross-link site between cysteine-83 of protein S13 and histidine-68 of protein S19 was established by microsequence analysis of isolated cross-linked peptides. This cross-link site was further confirmed by different analytical methods including fast atom bombardment mass spectrometry of the cross-linked peptide. The cross-linking site is located in the highly conserved C-terminal regions of proteins S13 and S19. In addition, the complete amino acid sequence of protein S13 from B. stearothermophilus is determined. Sequence comparison with the homologous Escherichia coli protein S13 revealed 58% identical amino acid residues.