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981.
B. Wang W. W. Xu J. Z. Wang W. Wu H. G. Zheng Z. Y. Yang J. D. Ray H. T. Nguyen 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1995,91(6-7):1111-1114
The thermo-sensititve genic male-sterile (TGMS) gene in rice can alter fertility in response to temperature and is useful in the two-line system of hybrid rice production. However, little is known about the TGMS gene at the molecular level. The objective of this study was to identify molecular markers tightly linked with the TGMS gene and to map the gene onto a specific rice chromosome. Bulked segregant analysis of an F2 population from 5460s (a TGMS mutant line) x Hong Wan 52 was used to identify RAPD markers linked to the rice TGMS gene. Four hundred RAPD primers were screened for polymorphisms between the parents and between two bulks representing fertile and sterile plants; of these, 4 primers produced polymorphic products. Most of the polymorphic fragments contained repetitive sequences. Only one singlecopy sequence fragment was found, a 1.2-kb fragment amplified by primer OPB-19 and subsequently named TGMS1.2. TGMS1.2 was mapped on chromosome 8 with a RIL population and confirmed by remapping with a DHL population. Segregation analysis using TGMS1.2 as a probe indicated that TGMS1.2 both consegregated and was lined with the TGMS gene in this population. It is located about 6.7 cM from the TGMS gene. As TGMS1.2 is linked to the TGMS gene, the TGMS gene must be located on chromosome 8.This research was supported by the Rockefeller Foundation and China National High-Tech Research and Development Program. The first author is a Rockefeller Career Fellow at Texas Tech University 相似文献
982.
Characterization of rapeseed myrosinase-binding protein 总被引:12,自引:0,他引:12
Myrosinase-binding proteins (MBPs) were purified from seeds of Brassica napus L. (oilseed rape). The proteins were characterized with respect to amino-acid composition, peptide sequence and isoelectric points. Gel electrophoresis and Western blotting of protein extracts from mature seeds showed the existence of at least ten proteins reacting with a monoclonal anti-MBP antibody and ranging in molecular size from 110 to 30 kDa. Proteins other than MBP reacting with the anti-MBP antibody were assigned as myrosinase-binding protein-related proteins (MBPRPs). Two MBPRPs were purified by immunoaffinity chromatography and characterized with respect to partial amino-acid sequence. Sequence identities were found between MBP and MBPRP. Western blot analysis of protein extracts from different tissues of B. napus showed that MBPRP is present in the whole plant, whereas MBP mostly occurs in the mature seed. A double-antibody sandwich enzyme-linked immunosorbent assay (ELISA) was used to investigate the occurrence of MBP and MBPRP in developing seeds of some species in the Brassicaceae family.Abbreviations FPLC
fast protein liquid chromatography
- MBP
myrosinase-binding protein
- MBPRP
myrosinase-bindingprotein-telated protein
- PBS
phosphate-buffered saline 相似文献
983.
Kwo-Feng Hsiao Fang-Lin Yang Shih-Hsiung Wu Kung-Tsung Wang 《Biotechnology letters》1995,17(9):963-968
Summary Regioselective ethanolysis of peracylated methyl , -D-glucopyranoside and methyl -D-mannopyranoside in anhydrous organic solvent (n-hexane/EtOH = 99/1) could afford 6-OH derivatives exclusively by Candida rugosa lipase (CRL). No 4 6 acyl migration was observed in such an anhydrous solvent system. Substrates with propanoyl groups were more reactive than with acetyl groups on CRL-catalyzed reactions. 相似文献
984.
Summary
Azotobacter chroococcum was grown in continuous culture at two temperatures (30 °C and 20 °C) and different dissolved oxygen tensions (DOT) (30 % to 40 % and 70 % to 80 % of air saturation), respectively. At the temperature of 30 °C and low DOT a relatively high volumetric productivity and efficiency of nitrogen fixation were obtained. After lowering the temperature to 20 °C, an intensive formation of cysts was observed associated with a drastic decrease of the bacterial growth. Bacteria in the form of cysts kept their physiological activity for a long period of time depending on temperature and preparation. 相似文献
985.
Deborah L. Weissenborn Cynthia J. Denbow Marko Laine Saara S. Lång Zhenbiao Yang Xueshu Yu Carole L. Cramer 《Physiologia plantarum》1995,93(2):393-400
Terpenoid phytoalexins and other defense compounds play an important role in disease resistance in a variety of plant families but have been most widely studied in solanaceous species. The rate-limiting step in terpenoid phytoalexin production is mediated by 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGR), which catalyzes mevalonic acid synthesis. HMGRs are involved in the biosynthesis of a broad array of terpenoid compounds, and distinct isoforms of HMGR may be critical in directing the flux of pathway intermediates into specific end products. Plant HMGRs are encoded by a small gene family, and genomic or cDNA sequences encoding HMGR have been isolated from several plant species. In tomato, four genes encode HMGR; these genes are differentially activated during development and stress responses. One gene, hmg 2 , is activated in response to wounding and a variety of pathogenic agents suggesting a role in sesquiterpene phytoalexin biosynthesis. In contrast, expression patterns of tomato hmg l suggest a role in sterol biosynthesis and cell growth. Other plant species show an analogous separation of specific HMGR isoforms involved in growth and/or housekeeping function and inducible isoforms associated with biosynthesis of phytoalexins or other specialized "natural products". We are applying a variety of cell and molecular techniques to address whether subcellular localization and/or differential expression of these isoforms are key factors in determining end product accumulation during development and defense. 相似文献
986.
H. Matsuoka H.-C. Yang T. Homma Y. Nemoto S. Yamada O. Sumita K. Takatori H. Kurata 《Applied microbiology and biotechnology》1995,43(1):102-108
Congo red was found to be feasible as a microscopic fluorescence indicator of hyphal growth at the single-hypha level. When 1 m Congo red was applied to mold of Aspergillus niger, the dye was found to a specific cell-wall component, chitin, without causing any inhibitory effect on hyphal growth. The bound Congo red emitted fluorescence at 614 nm. This binding reaction, however, proceeded more slowly than the growing speed of hypha. Consequently the fluorescence intensity was low at the apex where the surface area of the hypha was expanding rapidly. In contrast, as an apex where the growth was retarded, the fluorescence intensity became remarkably high. Therefore growing hyphae could be distinguished from non-growing hyphae by using Congo red. 相似文献
987.
988.
地衣芽孢杆菌β-甘露聚糖酶的纯化及酶学性质 总被引:6,自引:0,他引:6
地衣芽孢杆菌(Bacilluslicheniformis)NK-27菌株发酵产生的β-甘露聚糖酶(β-mannanase)经硫酸铵盐析沉淀,两次DEAE纤维素和SephadexG-100离子交换柱层析以及制备PAGE筹步骤,获得了凝胶电泳均一的样品。用SDS-凝胶电泳测得纯化后的β-甘露聚糖酶分子量为26kD,用凝胶聚焦电泳测得等电点PI为5.0。酶反应的最适pH为9.0,最后温度为60℃,稳定pH为6.0—9.0,稳定温度为40℃。金属离子中Mg ̄(2+)、Ca ̄(2+)、Fe ̄(2+)、Ni ̄(2+)对该酶有一定的激活作用;而Sn ̄(2+)、Zn ̄(2+)、Al ̄(3+)、Ag ̄+和Hg ̄(2+)对该酶有强烈的抑制作用。NK-27菌株的β-甘露聚糖酶对魔芋葡萄甘露聚糖和角豆胶半乳甘露聚糖的Km值分别为7.14和5.56mg·ml ̄(-1);V_(max)分别为200.53和157.45μmol·mg ̄(-1)·min ̄(-1)。 相似文献
989.
本文报道在云南南亚热燕山区大水体池塘中,用人工施肥培养浮游动物,作为革胡子鲶稚鱼的开口饵料及其形成夏花鱼苗的动物性饲料是可行的。对孵出四日龄的稚鲶进行培育,在水温23.2-30.3℃时,可使十七日龄稚鲶达到夏花水平,存活率达60%以上,研究结果表明,四日龄稚鲶口宽为760-900μm,开口期及生长前期主要摄取枝角类、桡足类和摇蚊幼虫。稚鲶生长后期,对轮虫、水生昆虫幼体及配合饲料的摄取量增加,而摄食 相似文献
990.
红头豆芫菁成虫芫菁素含量的研究 总被引:11,自引:0,他引:11
芫菁素在红头豆芫菁体内主要贮存在雄虫的生殖腺和卵内。与野生群体两性芫菁素的平均含量相比较,刚交配过的雄虫失去体内70%的芫菁素,其雌配偶体内芫菁素含量相应升高43%。红头豆芫菁可用作中药材。经110℃烘干后的雄虫,用酸水解后提取的芫菁素含量比直接提取的含量增高4倍。 相似文献