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T Mabuchi

Publications and source records attributed to T Mabuchi.

52 records · Page 3Linked to original sources
PubMed1994

Characterization of a species-specific DNA fragment originating from the Candida albicans mitochondrial genome.

A species-specific DNA fragment EO3 isolated from Candida albicans was characterized. EO3 was shown to originate from a duplicated region of C. albicans mitochondrial (mt) DNA. Nucleotide sequence of a 0.9 kbp fragment (EO3S) which confers the species specificity of EO3 was determined. EO3S region in some strains contained two parts of deletions (or insertions) of 50-60 bp with short inverted repeats at both ends. The EO3S region was maintained stably in mtDNA of individual C. albicans strains and may be useful as target DNA for the diagnosis and epidemiological studies of candidiasis.

Base Sequence↗
PubMed1993

New method for detection of Candida albicans in human blood by polymerase chain reaction.

We developed a new method for detection of Candida albicans cells in human blood by the polymerase chain reaction that amplifies a 125-bp region within a species-specific, multiple-copy DNA fragment. In preparing template DNA from C. albicans-containing blood, the addition of C. tropicalis cells, together with antibody which reacts with both cells, raised the sensitivity of detection of C. albicans to about 3 cells per 0.1 ml.

Base Sequence↗
PubMed1992

Isolation and characterization of a species-specific DNA fragment for detection of Candida albicans by polymerase chain reaction.

A 2-kbp DNA fragment, EO3, that was present in multiple copies in the Candida albicans genome was isolated for use in developing a detection method for C. albicans by polymerase chain reaction (PCR). Dot blot hybridization revealed that EO3 was specific for the 40 isolates of C. albicans serotypes A and B used. Using a set of primers (20-mer each) derived from the nucleotide sequence of EO3, we performed specific amplification of a 1.8-kbp DNA fragment within EO3 by PCR. All 40 isolates belonging to C. albicans serotypes A and B contained amplifiable 1.8-bkp fragments, although the DNA of the amplified products exhibited small variations in size, yielding three different fragment groups. Southern blot hybridization probed with EO3 showed that these 1.8-kbp fragments were derived from the EO3 region. Conversely, the 1.8-kbp fragment was not amplified from 38 isolates belonging to seven other medically important Candida species or from isolates of Cryptococcus neoformans, Saccharomyces cerevisiae, various bacteria, and a human cell line. The detection limit of the PCR assay for C. albicans with the EO3 fragment was shown to be approximately 2 to 10 cells and 100 cells in saline and human urine, respectively, by ethidium bromide staining and 2 and 10 cells, respectively, by Southern blot analysis. In addition, EO3 was assumed to originate from mitochondrial DNA on the basis of the results of its characterizations. These results indicate that the PCR system using the 1.8-kbp fragment as a target is a reliable method for identifying C. albicans isolates, thereby suggesting its potentials for specific and sensitive detection of C. albicans in samples from patients with candidiasis.

Base Sequence↗
PubMed1985

Cloning of mitochondrially determined oligomycin resistance, oli-1 in yeast.

An Escherichia coli-yeast shuttle vector pOL 221 is described, which consists of pBR 322 and a yeast mitochondrial fragment. The mitochondrial insert in pOL 221 possessed a mitochondrial autonomously replicating sequence (ARS) and a single Sst II site. The ARS function of pOL 221 was demonstrated by insertion of LEU2 gene into pOL 221 (giving pOL 2211) followed by the transformation of leu- yeast cells. By use of this vector, chimeric plasmids pOL 37 and pOL 379 (a derivative of pOL 37 inserted with LEU2 gene), carrying the yeast mitochondrial oli-I gene were constructed. Marked instability was observed on the maintenance of pOL 37 in E. coli under non-selective conditions. pOL 37 can, however, be maintained in E. coli in the presence of tetracycline. pOL 2211, pOL 379 and other pOL plasmids showed mitotic instability in yeast. Transformants of oligomycin sensitive yeast cells with pOL 37 and pOL 379 did not show oligomycin resistance. The absence of recombination between the cloned mitochondrial gene and the host mitochondrial gene is discussed.

Cloning, Molecular↗
PubMed1984

Nucleotide sequence of an essential region for autonomous replication of cloned yeast mitochondrial DNA.

A 341 bp sequence from yeast mtDNA was cloned, which consisted of an upstream 98 bp AT stretch and a downstream 206 bp AT stretch separated by a single 37 bp GC cluster. Cleavage of this GC cluster did not cause loss of the autonomously replicating function of this sequence. The recloned first 98 bp AT stretch was incapable of replication, while the recloned 206 bp AT stretch could replicate. We were able to confine an essential sequence for autonomous replication within a 186 bp AT stretch. Sequencing data revealed a sequence of ATATAAAT and stem and loop structures within the AT stretch.

Base Sequence↗
PubMed1984

Two autonomously replicating sequences near oli-1 gene of yeast mitochondrial DNA.

We cloned two autonomously replicating sequences from a short segment of mtDNA of an oligomycin-resistant petite yeast, O-111, into a vector pYleu 12 constructed from yeast LEU 2 gene and pBR 322. These plasmids, pYmit 4 and pYmit 1, had frequencies of transformation of yeast as high as that of YEp 13, having a replicator of 2 mu DNA. They were maintained as plasmids in yeast under selective conditions and shuttled from yeast to E. coli. No evidence was obtained that these plasmids were incompatible with the wild-type mitochondrial genome. These sequences were located in intergenic regions.

Base Sequence↗
PubMed1984

Nucleotide sequence involved in the replication of cloned yeast mitochondrial DNA.

A fragment of yeast mitochondrial DNA, Alu B, has two subfragments, Alu B1 and Alu B2. They were each cloned and sequenced. The autonomously replicating function of the curtailed Alu B1 (342 bp) was defined within 186 bp. A GC-rich sequence identical to the oris sequence in the curtailed Alu B1 was unnecessary for its autonomously replicating function. The 186 bp sequence had an ATATAAAT sequence and the stem and loop structures. The base sequence of Alu B2 also contained the same octanucleotides, the stem and loop structures, one oris sequence and one unique GC cluster. Yeast transformants with cloned Alu B2 grew slowly. The cloned Alu B2 was enlarged in the yeast host concomitantly with compensation of the slow growth of the transformants.

Base Sequence↗
PubMedDate not supplied

Mucinous cystadenoma with malignant transformation arising in the renal pelvis.

Mucinous cystadenoma with malignant transformation occupying the lower half portion of the right renal pelvis in a 69-year-old Japanese man was recorded. The patient had recent dysuria but no clinical history of pyelonephritis or urolithiasis. Under the clinical diagnosis of unusual renal cyst, the right total nephrectomy was performed. Grossly, the cystic tumor, 5 cm across, formed a monolocular lumen filled with mucins and showed no direct communication with the renal pelvis inside. Microscopically, the epithelial lining was characterized by a single layer of benign mucin producing columnar cells that scattered foci of non-invasive papillary projections with cell stratification and nuclear atypia suggestive of malignancy. Although there was non-specific chronic pyelitis, no pyelitis cystica et glandularis was encountered. Of circa 60 glandular neoplasms arising in the renal pelvis reported previously, adenomas are only five including two mucinous cystadenomas, while the remainder are adenocarcinomas. The histological findings of mucinous cystadenoma in the present case may represent the process of a transition from adenoma to adenocarcinoma. The result suggests the possibility that adenoma-carcinoma sequence may exist among the glandular neoplasma arising in the renal pelvis. The histogenesis was unclarified.

Aged↗