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11.
Debaryomyces vanrijiae MH201 produces formate oxidase (FOD) at estimated pI values by native isoelectric focusing of 5.1, 5.4, and 5.9. We cloned and expressed three formate oxidase cDNAs, FOD1, FOD2, and FDO3, of the yeast using Escherichia coli. The open reading frames of FOD1, FOD2, and FDO3 were 1,731 bp long, and encoded 576-amino acid polypeptides with molecular masses of 64,142, 63,794, and 63,836 Da respectively. Expression of FOD1, FOD2, and FOD3 resulted in the production of three isozymes, with pI values of 5.1, 5.9, and 5.9 respectively. Co-expression of FOD1 and FOD2 and of FOD1 and FOD3 resulted in the production of additional isozymes with pI values, of 5.4. The three amino acid sequences of FOD1, FOD2, and FOD3 contained a consensus motif of a flavin adenine dinucleotide binding site in their N-terminal parts and a glucose-methanol-choline oxidoreductase signature pattern, suggesting that formate oxidase ought to be classified in the glucose-methanol-choline oxidoreductase family.  相似文献   
12.
The 718,122 base pair (bp) sequence of the Escherichia coliK-12 genome corresponding to the region from 12.7 to 28.0 minuteson the genetic map is described. This region contains at least682 potential open reading frames, of which 278 (41%) have beenpreviously identified, 147 (22%) were homologous to other knowngenes, 138 (20%) are identical or similar to the hypotheticalgenes registered in databases, and the remaining 119 (17%) didnot show a significant similarity to any other gene. In thisregion, we assigned a cluster of cit genes encoding multienzymecitrate lyase, two clusters of fimbrial genes and a set of lysogenicphage genes encoding integrase, excisionase and repressor inthe e14 genetic element. In addition, a new valine tRNA gene,designated valZ, and a family of long directly repeated sequences,LDR-A, -B and -C, were found.  相似文献   
13.
The markless trout (iwame, Oncorhynchus iwame) has long been suspected not to be an independent species, but rather a markless mutant form of the red-spotted masu salmon (amago, O. masou ishikawae). Nevertheless, no field study has examined this issue. Here we report a field study on the reproductive ecology of iwame and amago coexisting in the upper stream of the Inabe River. We found that iwame and amago mate sympatrically, simultaneously, and randomly, and observed five cases of heterogeneous oviposition between the two. Our results suggest that no pre-mating reproductive isolation exists between iwame and amago. Because previous studies have shown the absence of post-mating isolation, we propose that iwame and amago are the same species. Iwame should be considered as a markless form of the red-spotted masu salmon, and O. iwame as a junior synonym of O. masou ishikawae.  相似文献   
14.
We examined the effects of oral L-hydroxyproline (Hyp) on collagen in the body. After 2 weeks' administration of Hyp (0.5 or 1 g/kg) to F344 male rats, the soluble collagen content of the skin had increased, and the serum concentration of collagen peptides was correlated with the skin content of soluble collagen. This result suggests that oral Hyp augmented collagen metabolism.  相似文献   
15.
Reproductive capacity was investigated in naturally occurring triploid individuals of the loach Misgurnus anguillicaudatus collected from Memanbetsu Town, Abashiri County, Hokkaido Island, Japan. These triploids have been considered to appear by accidental incorporation of the haploid sperm genome from normal diploid into unreduced diploid eggs from the clonal lineage that usually reproduces unisexually. By fertilization with sperm from the normal male, one triploid female gave many inviable aneuploid (2.1–2.7n) and very few tetraploid progeny, whereas the other produced both diploid and triploid progeny. The results suggest that at least four different types of eggs can be formed in triploid females in this locality. In contrast, no progeny hatched when eggs of the normal female were fertilized with sperm or sperm-like cells obtained from triploid males. These gametes exhibited inactive or no motility after adding ambient water. They had larger head sizes than those of normal haploid sperm and had a short or no tail. Although their ploidy was triploid or hexaploid, a small number of haploid cells were detected in the semen by flow cytometry. Thus, triploid males were generally sterile, but they have a little potential for producing very few haploid sperm.  相似文献   
16.
17.
Human epidermal growth factor receptor-2 (HER-2) overexpression in breast cancer occurs in 20% to 30% of patients with breast cancer. Trastuzumab (Herceptin) targets HER-2 tyrosine kinase receptors expressed on tumor cells and mediates anti-proliferative effects against HER-2-positive tumor cells. Adjuvant chemotherapy with trastuzumab has improved the prognosis of patients with HER-2 positive high-grade breast cancer. However, patients often experience appearance and proliferation of recurrent tumor cells after trastuzumab treatment. In this study, we report the successful establishment and characterization of a cell line (BTIC) derived from a patient with recurrent breast cancer after adjuvant chemotherapy with trastuzumab. Characteristics of the BTIC cell line were investigated by phase contrast or electron microscopic observations, chromosome analysis, xenotransplantation, immunohistochemistry and radioimmunoassay for tumor markers. We confirmed that the BTIC cell line grown as multilayered culture in culture dishes, has a poorly developed endoplasmic reticulum in the cytoplasm and some desmosomes. The population doubling time was approximately 44 hr. A graft in nude mouse after xenotransplantation was diagnosed as scirrhous carcinoma. Immunohistochemistry on cultured BTIC cells revealed that the BTIC cells were negative for estrogen receptor and progesterone receptor, and 30% positive for HER-2. Radioimmunoassay indicated secretion of HER-2 protein, NCC-ST-439 and CA15-3.  相似文献   
18.
We observed transient status-dependent female mimicry related to reproductive behaviour in landlocked red-spotted masu salmon (Oncorhynchus masou ishikawae). In females, the lower half of the lateral flank underwent solid blackening as an ovipositional character, and 70% of subordinate males showed a similar lateral pattern (M-type). In contrast, most of the paired males and 30% of subordinate males showed a different lateral pattern in which a melanic stripe ran along the lateral-line organ (N-type). It was possible to bring an M-type pseudo-fish model into closer proximity to a pair than an N-type model. In addition, the rate of successful sperm release in subordinate M-type males was higher than that in subordinate N-type males. Males could transform between N- and M-types according to fluctuations in competitive status among the males. A digital video image related to the article is available at .  相似文献   
19.
We successfully established a breast scirrhous carcinoma cell line (designated as NABCA) derived from metastatic tumors of the lymph node. The cells grew as multi-layered cultures without contact inhibition. The population doubling time was approximately 66 h. G-band karyotype of NABCA revealed 66% diploid, XX. Surprisingly, the cells had a number of secretory granules and straight microvilli as a brash border. In heterotransplantation, the cells produced a tumor resembling the original tumor. The NABCA is sensitive to Adriamycin (doxorubicin; KYOWA HAKKO KOGYO, Tokyo, Japan) and Taxol (paclitaxel; Bristol-Myers KK, Tokyo, Japan). This cell line is useful for studying the mechanism of lymphatic metastasis and susceptibility of anticancer drugs in human breast scirrhous cancer.  相似文献   
20.
To "mark" the nitrogen atoms in phenyl-(2-pyridyl)-(3-pyridyl)-(4-pyridyl)methane (1), we have synthesized the corresponding tris(pyridine N-oxide) 2 by oxidation of 1 with m-chloroperbenzoic acid. The nitrogen atoms of 2 are unequivocally determined by the X-ray crystal analysis of a single crystal of rac-2 whereas the nitrogen atoms cannot be assigned at all in the case of rac-1. N-Oxide 2 can be resolved by chiral high-performance liquid chromatography under similar conditions to those used for the resolution of 1. The calculated circular dichroism (CD) curve for (R)-2 on the basis of time-dependent density functional theory reproduces the experimental spectra very well to suggest that the second-eluted fraction ([CD(+)283]-2) is the R isomer, namely (R)-[CD(+)283]-2. The independent absolute configuration determinations for 1 and 2 are in keeping with the chemical correlation between the two compounds by oxidation of (R)-1 into (R)-2.  相似文献   
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