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J Kudoh

Publications and source records attributed to J Kudoh.

119 records · Page 7Linked to original sources

Amino-terminal structure of spoOA protein and sequence homology with spoOF and spoOB proteins.

The previously reported nucleotide sequence of the spoOA coding region of Bacillus subtilis suggested that the protein is initiated with either of two possible initiation codons, ATG and GTG, 84 base pairs apart. To determine which codon is utilized as an initiator in B. subtilis, we constructed a fusion gene in which the promoter and NH2-terminal region of the spoOA gene was connected to the chloramphenicol acetyltransferase gene (cat gene). After introduction of the plasmid carrying the spoOA-cat fusion gene into B. subtilis cells, the fusion protein was purified by affinity chromatography. The sequence of NH2-terminal amino acids of the fusion protein was determined and the result established that the GTG codon is utilized as an initiator in B. subtilis. Comparison of the amino acid sequences revealed a marked homology between the spoOA (NH2-terminal half) and spoOF proteins. A less striking but significant homology was also found between the spoOA (COOH-terminal half) and spoOB proteins. This suggests the presence of a common functional domain structure for these proteins that are supposed to play key regulatory roles in sporulation.

Acetyltransferases↗

Nucleotide sequences of the sporulation gene spo0A and its mutant genes of Bacillus subtilis.

We have determined the nucleotide sequence of a 2375-base-pair DNA fragment, which contained the sporulation gene spo0A cloned from Bacillus subtilis. The sequence had only one long open reading frame consisting of 239 codons, which was found to correspond to the spo0A gene by comparing the nucleotide sequence of the wild-type gene with those of the mutant alleles. The calculated molecular weight of the product of the wild-type spo0A gene was 26,500. We found also a new mutation, sgi, which maps within the spo0A gene. This mutation relieves the growth inhibition of the host cells caused by a multicopy plasmid carrying the spo0A gene. The mutations spo0A12, spo0C9V, and sgi-1 were found to be an amber mutation at the 62nd codon, a missense at the 229th codon, and a frame-shift at the 223rd codon of the spo0A gene, respectively.

Bacillus subtilis↗

Genetic analysis of spo0A and spo0C mutants of Bacillus subtilis with a phi 105 prophage merodiploid system.

An 8.0-kilobase chromosomal fragment of Bacillus subtilis which contained an intact spo0A gene was recloned onto temperate phage phi 105 from the rho 11dspo0A+-1 transducing phage. A specialized transducing phage, phi 105-dspo0A+-1, was constructed and used to transduce the spo0A12 mutant strain 1S9. A Spo+ transductant which was a single lysogen of the phi 105dspo0A+-1 transducing phage was isolated. From competent cells of this Spo+ transductant was isolated a Spo- (Spo0A) strain which was immune to phi 105. It was used to prepare a lysate of the phi 105dspo0A12 phage. Transduction of the spo0C9V recE4 strain with the phi 105dspo0A12 and phi 105dspo0A+-1 phages was carried out. The phi 105dspo0A+-1 phage gave rise to a large number of heat-resistant cells, but the phi 105dspo0A12 phage formed no heat-resistant cells. These results indicate that the spo0A12 and spo0C9V mutant genes do not complement each other in the ability to sporulate and that the spo0C9V mutation is located within the spo0A gene. Although the spo0C9V strain was completely asporogenous, the spo0C9V/spo0C9V diploid strain produced heat-resistant cells at a frequency of ca. 10(-3) in the sporulation medium. This result indicates that two copies of the spo0C9V mutant gene partially restore the ability of these cells to sporulate.

Alleles↗

Identification of the sporulation gene spoOA product of Bacillus subtilis.

A 2.4-kilobase fragment of the Bacillus subtilis chromosome containing the wild-type spoOA gene derived from the phi 105dspoOA+-Bc-1 transducing phage was cloned onto plasmid pBR322 in Escherichia coli. A recombinant plasmid harboring the mutant spoOA12 allele on the 2.4-kilobase insert was also constructed from the phi 105dspoOA12-1 phage DNA and pBR322. Protein products synthesized in response to plasmid DNA in a DNA-directed cell-free system derived from E. coli were analyzed by sodium dodecyl sulfate-polyacryl-amide gel electrophoresis. A protein of approximately 27,500 daltons synthesized with the recombinant plasmid DNA harboring the wild-type spoOA gene as template was not formed with the recombinant plasmid DNA harboring the spoOA12 allele. Since the spoOA12 mutation is a nonsense mutation, we conclude that the 27.5-kilodalton protein is the product of the spoOA gene.

Alleles↗

Cloning of sporulation genes spo0A and spo0C of Bacillus subtilis onto rho 11 temperate bacteriophage.

A HindIII fragment harboring the intact spo0C gene of Bacillus subtilis was cloned with rho 11 temperate bacteriophage as a vector. Transformation experiments with the DNA from rho 11 dspo0C+ specialized transducing phage showed that the spo0C gene resides on a 5.3-megadalton fragment generated by HindIII digestion. The 5.3-megadalton fragment also contains the intact spo0A gene, but not spoIIIA, spoIIIB, or spoIVB.

Bacillus subtilis↗

[A study on the possible transmission of hepatitis B virus from HBsAg carrier women to their husbands (author's transl)].

In order to assess the possible sexual transmission of hepatitis B virus (HBV), the occurrence of post-marital acute hepatitis and the prevalence of hepatitis B surface antigen (HBsAg) and antibody (HBsAb) were investigated among the husbands of HBsAg carrier women. The possible infectious routes and influencing factors in the HBV infection of the husbands by their HBsAg carrier wives were also discussed. This study demonstrates: 1. In the husbands examined, the exposure marker of HBV was found to be 32.8 per cent and the occurrence rate of post-marital hepatitis came up to 7.2 per cent. 2. The transmission of HBV from HBsAg carrier women to their husbands was supposed to take place shortly after marriage. E-Ag and e-Ab in ther sera of HBsAg carrier women could serve respectively as indicators of positive and negative HBV transmission. In the husbands with wives whose serum HBsAg-titers by R-PHA were higher than 39, a high exposure marker of HBV (87.5%) was observed. 3. The results of HBsAg detection rates and titers in various kinds of body fluids obtained from HBsAg carrier women suggested that cervical mucus and vaginal discharge might play an important role in the sexual HBV transmission.

Carrier State↗

Sexual transmission of hepatitis B surface antigen. Infection of husbands by HBsAg carrier-state wives.

The husbands of 68 hepatitis B surface antigen (HBsAg) carrier-state wives were tested for the presence of hepatitis B surface antibody (HBsAb) and antigen (HBsAg) to assess possible transmission of HBsAg. Eight (11.8%) of the 68 husbands gave negative results for HBsAg and 22 (32.4%) positive results for HBsAb. Furthermore, eight (26.7%) of 30 husbands with presumed HBsAg transmission from their wives developed acute viral hepatitis after marriage, and e antigen (eAg) was detected in the serum from all eight wives. Although HbsAg was not detected in specimens of sputum and cervical mucus of carrier-state women by reverse passive haemagglutination, it was detected in the vaginal discharge of women during days 1--6 of the menstrual cycle at a rate ranging from 20--60%. Thus, sexual transmission of HBsAg seems to occur, particularly if sexual contact takes place during or immediately after menstruation.

Carrier State↗

Diagnosis and molecular analysis of an atypical case of holocarboxylase synthetase deficiency.

Holocarboxylase synthetase (HCS) deficiency is a disorder of biotin metabolism characterised by metabolic ketoacidosis and skin lesions due to reduced activities of multiple biotin-dependent carboxylases. The onset of this disease is usually between the neonatal and infantile period. Here we report the molecular analysis of an atypical case of HCS deficiency, where the patient developed his first episode of acidosis at age 8 years and had an exceptionally slow response to biotin therapy. A homozygous mutation was identified at the + 5 position of the splice donor site in intron 10 of the HCS gene (IVs10 + 5(g-->a)), resulting in abnormal splicing of HCS mRNA. A moderate decrease in the amount of normal HCS mRNA may account for the atypical, late-onset phenotype of this patient. Conclusion Molecular analysis is a useful tool for understanding the phenotypic variations in holocarboxylase synthetase deficiency.

Age of Onset↗

The value of dynamic MR imaging for hypointensity lesions of the peripheral zone of the prostate.

The aim was to evaluate the role of dynamic magnetic resonance (MR) imaging for prostatic carcinoma. Forty-two men with clinical suspicion of a prostatic carcinoma underwent MR imaging. Dynamic MR was performed, followed by postcontrast T1-weighted imaging with fat suppression. Histologic diagnosis was 21 prostatic carcinomas (in 19 patients), 21 benign tissues, and 2 chronic prostatitis. The diagnostic accuracy was 75% for T2-weighted images, and 79% for dynamic images. The accuracy of the combination of dynamic MR images with postcontrast T1-weighted images was 82%. It was concluded that dynamic MR imaging was useful in differentiation of low intensity lesions in the peripheral zone.

Aged↗