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T Takao

Publications and source records attributed to T Takao.

At least 235 records · Page 13Linked to original sources
PubMed1985

Amino acid sequence of heat-stable enterotoxin produced by Vibrio cholerae non-01.

The amino acid sequence of heat-stable enterotoxin, produced by Vibrio cholerae non-01 and isolated from its culture supernatant, was determined by both Edman degradation of native and reductively carboxymethylated enterotoxin and also a combination of fast atom bombardment mass spectrometry and carboxypeptidase Y digestion of native enterotoxin to be as follows: Ile-Asp-Cys-Cys-Glu-Ile-Cys-Cys-Asn-Pro-Ala-Cys-Phe-Gly-Cys-Leu-Asn. This sequence is very similar, but not identical, to those of heat-stable enterotoxins produced by enterotoxigenic Escherichia coli and Yersinia enterocolitica.

Amino Acid Sequence↗
PubMed1985

Isolation, primary structure and synthesis of heat-stable enterotoxin produced by Yersinia enterocolitica.

Five heat-stable enterotoxins were isolated from the culture supernatant of Yersinia enterocolitica and purified to homogeneity by DEAE-Sephacel and high-performance liquid chromatographies. They caused acute fluid accumulation in the intestine of suckling mice. The amino acid sequence of one of the enterotoxins was determined to be Ser-Ser-Asp-Trp-Asp-Cys-Cys-Asp-Val-Cys-Cys-Asn-Pro-Ala-Cys-Ala-Gly-Cys, by Edman degradation of its pyridylethylated derivative and a combination of fast atom bombardment mass spectrometry and carboxypeptidase B digestion. This structure was unambiguously confirmed by chemical synthesis. The other enterotoxins had longer or shorter amino acid sequences at their N termini, but the same sequence at their C termini. The six half-cystine residues formed intramolecular disulfide linkages, as shown by measurement of the molecular masses of the enterotoxins by fast atom bombardment mass spectrometry. The sequence of 13 amino acid residues at the C terminus showed similarity to those of heat-stable enterotoxins isolated from enterotoxigenic Escherichia coli [Aimoto, S. et al. (1982) Eur. J. Biochem. 129, 257-263; Takao, T. et al. (1983) FEBS Lett. 152, 1-5] suggesting that these similar sequences are related to the common biological and immunological properties of enterotoxins produced by Y. enterocolitica and enterotoxigenic E. coli.

Amino Acid Sequence↗
PubMed1985

Verification by mass spectrometry of the primary structure of human interleukin-2.

Proteolytic digests of interleukin-2 from a human leukemic T-cell line produced by Escherichia coli carrying a recombinant DNA were analyzed by fast atom bombardment mass spectrometry. The mass values of intense signals observed in the mass spectrum were consistent with peptides predicted from the nucleotide sequence of cDNA for human interleukin-2, an indication that the protein with the predicted amino acid sequence was produced by E. coli. BrCN and proteolytic digests of interleukin-2 obtained from cultured cells were also examined by fast atom bombardment mass spectrometry. The observed mass values were identical with those from interleukin-2 from E. coli except for that of the NH2-terminal sequence, in which the Thr residue at position 3 was bound to a sugar moiety. The mass spectra of the digests of the two interleukin-2 preparations and synthetic peptides with sequences from 117 to 128 and 121 to 128 predicted from the nucleotide sequence of cDNA for a human interleukin-2 indicated that Cys residues at positions 58 and 105 are linked by a disulfide bond and that the Cys residue at position 125 is free.

Amino Acid Sequence↗
PubMed1985

Facile identification of protein sequences by mass spectrometry. B subunit of Vibrio cholerae classical biotype Inaba 569B toxin.

A mass spectrometric method was applied to the B subunit of Vibrio cholerae classical biotype Inaba 569B toxin to determine its amino acid sequence and to confirm the differences in the amino acid sequences predicted from the nucleotide sequences of the genes of El Tor biotype strains 62746 and 2125 toxins. In this method, the Staphylococcus aureus protease V8 digest of the CNBr-treated B subunit of the classical biotype toxin was examined directly by fast-atom-bombardment mass spectrometry without separation of individual peptides. The values of molecular ion signals observed in the mass spectra were compared with the amino acid sequences of the classical biotype and El Tor biotype toxins. All the observed mass values coincided with those calculated from the published sequences of the B subunit except those of the sequences at positions 12-29 and 69-79. Peptides with these sequences were isolated by high-performance liquid chromatography and analyzed by Edman degradation or by combination of mass spectrometry and enzymatic degradation. The results revealed that the amino acid residues at positions 22 and 70 were Asp instead of Asn in the published sequences of classical biotype toxin. It was also found that Asn at position 44 was partially deaminated to Asp. The amino acid sequence of the classical biotype toxin was found to be different only at positions 18 (His----Tyr), 47 (Thr----Ile) and 54 (Gly----Ser) from that of El Tor biotype toxins.

Amino Acid Sequence↗
PubMed1985

Complete amino acid sequence of the ubiquinone binding protein (QP-C), a protein similar to the 14,000-dalton subunit of the yeast ubiquinol-cytochrome c reductase complex.

The amino acid sequence of the ubiquinone binding protein (QP-C) in the cytochrome bc1 region of the mitochondrial electron transfer chain was determined by analysis of peptides obtained by cyanogen bromide cleavage and staphylococcal protease digestion of succinylated derivatives. It was found to consist of 110 amino acid residues and its amino terminus to be blocked by an acetyl group, as determined by mass spectrometry of the amino-terminal peptide and a comparison with peptides chemically synthesized on high-performance liquid chromatography. The molecular weight of this ubiquinone binding protein including the acetyl group was calculated to be 13,389. The predicted secondary structure of QP-C has alpha-helical content of about 50% and QP-C was classified as an "all-alpha" or "alpha + beta" protein. This is the first report describing the amino acid sequence of the ubiquinone binding protein. A comparison of this sequence with that of the 14-kDa subunit of the yeast ubiquinol-cytochrome c reductase complex from the nucleotide sequence showed these two sequences to be quite similar.

Amino Acid Sequence↗
PubMed1985

Congenital absence of small intestinal musculature (one case report).

Intestinal obstruction due to congenital absence of the small intestinal musculature in a neonate is presented. This report represents the seventh known case of this abnormality. In addition, in our case ectopic oesophageal mucosa and ectopic gastric mucosa is detected. The aetiology of this condition is unknown, and the diagnosis must simply depend on pathological examination of biopsy samples taken from appropriate regions. Unfortunately the regions of this disease have no continuity. Therefore, course of treatment cannot be established as the extent of the region cannot be correctly identified. To detect change of colour tone of the bowel may be helpful in the treatment of the disease.

Female↗
PubMed1985

Subtilosin A, a new antibiotic peptide produced by Bacillus subtilis 168: isolation, structural analysis, and biogenesis.

Subtilosin A, a new antibiotic produced by Bacillus subtilis 168, was extracted from culture medium with n-butanol and purified to homogeneity by a combination of gel filtration and thin-layer chromatography. The yield was 5.5 mg from a liter of culture. It had bacteriocidal activity against some gram-positive bacteria. Amino acid analysis and mass spectrometry showed that it was a peptide with a molecular weight of 3398.9, consisting of 32 usual amino acid and some non-amino acid residues. Its amino- and carboxyl-termini were blocked. By analysis of the fragments obtained by partial acid hydrolysis, as well as by chymotryptic and thermolysin digestions of reduced and S-carboxymethylated samples and Achromobacter protease I digestion of performic acid-oxidized samples, the amino acid sequence was determined to be as follows: X-Gly-Leu-Gly-Leu-Trp-Gly-Asn-Lys-Gly-Cys-Ala-Thr-Cys-Ser-(sequence; see text) Ile-Gly-Ala-Ala-Cys-Leu-Val-Asp-Gly-Pro-Ile-Pro-Asp-Glx-Ile-Ala-Gly-Ala. The analyses of cross-linking structures revealed that there were linkages between the amino- and carboxyl-termini and between the Cys-19 and the Glx-28 residues through an unknown residue with a residue weight of 163. Consequently, subtilosin A was deduced to be a cyclic peptide antibiotic with a novel cross-linking structure. The production of subtilosin A begins at the end of vegetative growth and finishes before spore formation. Studies on the correlation between the production of subtilosin A and spore formation with decoyinine in the original strain and in asporogenous mutants of B. subtilis 168 suggested that there was no close correlation between the two phenomena. The production of subtilosin A was repressed by inhibitors of protein and RNA synthesis in contrast to that of many other antibiotic peptides, suggesting that it is synthesized by the mechanism of usual protein synthesis.

Amino Acid Sequence↗
PubMed1984

Primary structure of heat-stable enterotoxin produced by Yersinia enterocolitica.

A heat-stable enterotoxin was isolated and purified from the culture supernatant of Yersinia enterocolitica by reversed-phase high-performance liquid chromatography. The amino acid sequence of the purified toxin was determined to be as follows: (sequence; see text) (X: not determined). The C-terminal sequence containing 6 half-cystine residues was highly homologous to that of heat-stable enterotoxin of enterotoxigenic Escherichia coli.

Amino Acid Sequence↗
PubMed1984

Verification of protein sequence by fast atom bombardment mass spectrometry. Amino acid sequence of protein S, a development-specific protein of Myxococcus xanthus.

A mass spectrometric method was applied to protein S, a development-specific protein of Myxococcus xanthus, in order to verify the amino acid sequence deduced from the nucleotide sequence of its gene. On examining proteolytic digests of the protein by fast atom bombardment mass spectrometry without separation of individual peptides, signals corresponding to individual peptides were observed in the mass spectra. The mass values of the observed signals were correlated to the theoretical mass values calculated from the predicted amino acid sequence, thereby identifying the peptides and proving the accuracy of the sequence. The previous finding that protein S is the product of the second gene of the two tandemly repeated genes on the M. xanthus chromosome ( Inouye , S., Franceschini , T., and Inouye , M. (1983) Proc. Natl. Acad. Sci. U.S.A. 80, 6829-6833) is now unambiguously confirmed.

Amino Acid Sequence↗
PubMed1983

Amino acid sequence of a heat-stable enterotoxin isolated from enterotoxigenic Escherichia coli strain 18D.

A heat-stable enterotoxin produced by a strain of enterotoxigenic Escherichia coli 18D was purified by ion-exchange and reversed-phase high-pressure liquid chromatography. The amino acid sequence of the purified toxin was determined by Edman-degradation and a combination of fast atom bombardment mass spectrometry and carboxypeptidase digestion to be Asn-Thr-Phe-Tyr-Cys-Cys-Glu-Leu-Cys-Cys-Asn-Pro-Ala-Cys-Ala-Gly-Cys-Tyr.

Amino Acid Sequence↗
PubMed1983

Computed tomography in postinfluenzal encephalitis.

A 2-year-old girl developed encephalitis following influenza A virus infection. Brain computed tomography (CT) showed symmetrical hypodense areas in the putamina. Contrast enhancement was noted surrounding the hypodense areas 2 days after the onset of encephalitis. These localized lesions demonstrated on CT have not been reported in the literature of postinfluenzal encephalitis.

Child, Preschool↗
PubMed1983

Sequential CT studies of 24 children with infantile spasms on ACTH therapy.

Sequential CT studies were performed in 24 patients with infantile spasms, before, during and after ACTH therapy, in order to analyze the relationship between the dose of ACTH and changes in CT scan findings. In six cases CT scans did not return to their original state after ACTH therapy. Two illustrative cases are reported. There was a good correlation between the total dose of ACTH and the percentage decrease of brain parenchyma. It is concluded that 'cerebral atrophy' on CT scans may represent an accumulative effect of ACTH and that ACTH should be given with the utmost discretion, and in as low a dose as possible.

Adrenocorticotropic Hormone↗
PubMed1982

Amino-acid sequence of a heat-stable enterotoxin produced by human enterotoxigenic Escherichia coli.

A heat-stable enterotoxin produced by a human strain of enterotoxigenic Escherichia coli was extensively purified by reverse-phase high-performance liquid chromatography. The minimum effective dose of the purified toxin to cause fluid accumulation in suckling mice was 2.5 ng. The amino acid sequence of the purified toxin was determined by Edman degradation and a combination of fast atom bombardment mass spectrometry and carboxypeptidase digestion to be Asn-Ser-Ser-Asn-Tyr-Cys-Cys-Glu-Leu-Cys-Cys-Asn-Pro-Ala-Cys-Thr-Gly-Cys-Tyr. This sequence was identical to that deduced from the nucleotide sequence encoding a human heat-stable enterotoxin, reported by Moseley et al., except for the C-terminal Tyr residue.

Amino Acid Sequence↗