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941.
Individual phospholipids were assayed in exponentially growing and G1-arrested temperature-sensitive cell division cycle (cdc) mutants of Saccharomyces cerevisiae. It was observed that cdc28 cells which are known to arrest at ‘start’ when shifted to their non-permissive temperature, resulted in a 40% decrease in phosphatidylinositol (PI) level while the phosphatidylserine (PS) content was doubled in these cells. The reduced level of PI was restored in cdc4 and cdc7 mutants which are known to arrest past the ‘start’. The increase in PS level in cdc8 mutant which was probably to compensate the intrinsic charging of membrane environment, was also reduced in cdc4 and cdc7 mutants. Our results demonstrate that PI may play a role in yeast cell division and growth that the abnormalities of cdc28 could also be related to PI decrease. 相似文献
942.
Tetsuya Tachikawa Kimitaka Kamikawa David Chia Yukinori Sameshima Shen Son Mo Shin Yazawa Anil K. Singhal Sen-itiroh Hakomori Paul I. Terasaki 《Glycoconjugate journal》1984,1(2):111-117
A microenzyme-linked immunosorbent assay system employing monoclonal antibody SNH3 was developed for the detection of sialosyl Lewisx antigen in stool extracts from 80 patients with colorectal cancer, 13 patients with colorectal non-malignant disorders and 90 normal subjects. Sialosyl Lewisx antigen was detected in 35% of stool extracts from cancer patients but only in 7.7% and 2.2% of those from non-malignant patients and normal subjects respectively. Hemoglobin in the same stool samples was detected in 37.5% of cancer patients, 15.4% of non-malignant patients and 5.6% of normal subjects. The appearance of sialosyl Lewisx antigen in stool was not necessary correlated with that of hemoglobin, and overall 61.3% of cancer patients were detected by the combination of the two assays. The combination assay was also impressive in early detection of colorectal cancer (Dukes' A, 52%; Dukes' B, 57.1%). Therefore, the assay for sialosyl Lewisx antigen in stool would be useful for detecting colorectal cancer. 相似文献
943.
944.
Sequences responsible for the tissue specific promoter activity of a pea legumin gene in tobacco 总被引:17,自引:0,他引:17
Anil Shirsat Neville Wilford Ronald Croy Donald Boulter 《Molecular & general genetics : MGG》1989,215(2):326-331
Summary Maturing pea cotyledons accumulate large quantities of storage proteins at a specific time in seed development. To examine the sequences responsible for this regulated expression, a series of deletion mutants of the legA major seed storage protein gene were made and transferred to tobacco using the Bin19 disarmed Agrobacterium vector system. A promoter sequence of 97 bp including the CAAT and TATA boxes was insufficient for expression. Expression was first detected in a construct with 549 bp of upstream flanking sequence which contained the the leg box element, a 28 bp conserved sequence found in the legumintype genes of several legume species. Constructs containing-833 and-1203 bp of promoter sequence significantly increased levels of expression. All expressing constructs preserved seed specificity and temporal regulation. The results indicate that promoter sequences between positions-97 and-549 bp are responsible for promoter activity, seed specificity, and temporal regulation of the pea legA gene. Sequences between positions-549 and-1203 bp appear to function as enhancer-like elements, to increase expression. 相似文献
945.
Summary Cadmium-resistant strains of the cyanobacterium Nostoc calcicola were isolated through the step-wise transfer of the organism to higher levels of the metal. One of the Cd-resistant strains (Cdr–10) showed cross-resistance to antibiotics like neomycin (1 g/ml), chloramphenicol (3 g/ml) but not to streptomycin. The Cd-resistant strain also tolerated elevated levels of metals such as zinc (20 ppm) and mercury (1 ppm). The stability of the metal-resistance required the presence of Cd2+ ions in the growth medium. It is suggested that metal resistance may also be determined by gene(s) on the antibiotic resistance plasmids in cyanobacteria. 相似文献
946.
Anil Kumar R.R. Ernst K. Wüthrich 《Biochemical and biophysical research communications》1980,95(1):1-6
The recently developed technique of two-dimensional (2D) cross-relaxation spectroscopy is utilized for systematic measurements of selective nuclear Overhauser enhancements (NOE) in the high resolution 1H nuclear magnetic resonance (NMR) spectra of biological macromolecules in solution. Compared to conventional one-dimensional NOE studies, the 2D NOE experiment has the principal advantage that it avoids detrimental effects arising from the limited selectivity of preirradiation in crowded spectral regions. Furthermore, it yields with a single instrument setting a complete network of NOE's between all the protons in the macromolecule. The resulting information on intramolecular proton-proton distances provides a new avenue for studies of the spatial structures of biopolymers. 相似文献
947.
UDP-galactose:ceramide galactosyltransferase of rat central-nervous-system myelin. 总被引:1,自引:0,他引:1
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The properties of ceramide galactosyltransferase associated with myelin and microsomal fractions of rat brain were studied. The enzyme from both the fractions had similar properties during development and synthesized the same molecular species of the product cerebroside. The results suggested that during myelination the turnover rate of enzyme protein is altered instead of regulatory modulation of the enzyme protein. 相似文献
948.
Suman Khowala Anil Kumar Ghosh Subhabrata Sengupta 《Applied microbiology and biotechnology》1992,37(3):287-292
Summary An amyloglucosidase from a mycelial culture of the mushroom Termitomyces clypeatus hydrolysed larch wood xylan independently and synergistically with an endo-(14) xylanase of the same fungus. The glucoamylase saccharified xylan predigested with xylanase at a faster rate compared to that of xylanase acting on amylase-digested xylan. However, overall saccharification of xylan in both cases was the same. Only glucose was liberated from xylan by amylase digestion whereas xylose, xylobiose and other oligosaccharides were liberated during xylanase digestion. The synergistic response of enzyme combinations was reflected in the liberation of glucose from xylan, rather than xylose. Glucoamylase and xylanase activities on soluble and insoluble fractions of larch wood xylan with different xylose and glucose contents suggested that synergism in xylanolysis by the presence of glucoamylase was dependent on the activity of the participating xylanase on the xylan preparation. It is suggested that possibly -glucosidic linkages are present in xylan and that amyloglucosidase might be involved in xylanolysis.
Correspondence to: S. Sengupta 相似文献
949.
Immunocytochemical localization studies revealed the presence of 10·5 kDa inhibin in the prostatic epithelial cells of the
human, non-human primates (Macaca radiata,Presbytis entellus, Callithrix jacchus), dog and laboratory rodents (guinea pigs, hamsters, rats and mice). The capability of the prostate gland to synthesize inhibinin vitro was shown by the incorporation of radiolabeled leucine into inhibin which was immuno-precipitated. Unlike most prostatic
proteins, inhibin was found to be androgen-independent since no significant alteration in inhibin concentration in prostate
occurred pre/post castration. Physicochemical and immunological characteristics of inhibin as revealed by high performance
liquid chromatography and parallel dilution curve in a radioimmunoassay revealed similarities of inhibin in prostates of various
species. 相似文献
950.
We evaluated 151 coded isolates of medically important yeast species belonging to the genera Candida, Cryptococcus, Geotrichum, Rhodoturula, Saccharomyces and Torulopsis using the newly developed rapid Pro-Lab Identification Ring, PL 960 system (PLID-Ring). All isolates were concurrently identified by the API 20C and conventional procedures comprising macro- and micromorphology, assimilation and fermentation of various carbon and nitrogen compounds. The PLID-Ring system identified isolates of Candida albicans, C. kefyr, C. krusei, C. lusitaniae, C. parapsilosis, Rhodotorula rubra, and Torulopsis glabrata with 100% accuracy in 24 h. This system identified C guilliermondii and S. cerevisiae isolates with an accuracy of 90% and 86%, respectively, while those belonging to Cr. neoformans, T. candida (= C. famata), C. rugosa and C. tropicalis were identified with 38.4%, 50%, 12.5% and 50% accuracy, respectively. Three isolates of Cr. laurentii were not identified by the PLID-Ring system. The overall accuracy of the PLID-Ring system was 81.45% (123 of 151 isolates). However, the system does not include species such as Cr. laurentii in its data base. When these three Cr. laurentii isolates were excluded from the evaluation, the accuracy of the PLID-Ring system increased from 81.45% to 83.1%. 相似文献