查看文章

A protein of Mr 26,000 which was present in large quantities in extracts of cells of Helicobacter pylori was purified to homogeneity by ammonium sulfate precipitation followed by gel filtration and reversed-phase chromatography or anion-exchange chromatography. The protein appeared to be associated with the soluble fraction of the cell, and antibodies raised against the protein were reactive with whole-cell lysates of a variety of H. pylori strains in a simple immunodot blot assay. This reaction was species specific. Protein sequence determination of the amino terminus and internal cyanogen bromide fragments and amino acid composition analysis were performed. An oligonucleotide derived from these data was used to clone a fragment encoding most of the coding sequence. Expression in Escherichia coli was dependent on vector promoters. The DNA sequence of the fragment was determined. DNA probes …