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991.
Chitinase,β-1,3-glucanase, cellulase, xylanase and protease activity were detected in a crude enzyme preparation obtained from a slime
mold (Badhamia utricularis) which was grown on autoclaved mycelia ofPholiota nameko in a petri dish. The optimal pH of the enzyme preparation for lytic activity against fruit bodies ofLentinus edodes was 4.0, and those ofβ-1,3-glucanase and cellulase were the same. On the other hand, chitinase and protease showed optimal activity at pH 5.0 and
8.0, respectively. The lytic activity was stable below 40°C but completely inactivated at 70°C, and was most stable at pH
5.0. The studies of the optimal pH, thermal stability, and pH stability, and isoelectric focusing analysis of the enzyme preparation
suggest that chitinase,β-1,3-glucanase and cellulase activities may be responsible for lysis of fruit bodies of some mushrooms. The crude enzyme preparation
from the slime mold lysed fruit bodies of several mushrooms more efficiently than did commercial lytic enzymes preparations
(Driselase and Usukizyme). 相似文献
992.
993.
994.
Y Oomori S Okuno H Fujisawa K Ishikawa Y Satoh M Matsuda M Yamano K Ono 《Acta anatomica》1989,136(1):49-54
The present study applied the separated adrenal capsules of rats for wholemount immunocytochemistry and used tyrosine hydroxylase (TH) antibody as a marker for catecholamines. TH-immunoreactive nerve bundles without varicosities and fibers with varicosities were seen to run along or to encircle blood vessels entering the adrenal capsule from the outside, and then to run along a network of blood vessels in the intracapsular region. Also, the TH-immunoreactive nerve bundles and fibers were found to run along blood vessels in the subcapsular region. Some TH-immunoreactive nerve fibers and bundles with varicosities, unassociated with the blood vessels, were seen in the subcapsular region. In this region, TH-immunoreactive nerve fibers with varicosities were often seen to be closely associated with the cortical cells. Some TH-immunoreactive nerve fibers without varicosities were visible within the splanchnic nerve in the subcapsular region. The present study suggests that numerous catecholaminergic nerve fibers are associated with blood vessels forming a network in the superficial region of the rat adrenal gland. 相似文献
995.
996.
Summary Reflecting chromatophores in the dermis of the skin of a freshwater goby, Odontobutis obscura, are of an iridophore type. These chromatophores contain numerous reflecting platelets, which are similar to those in iridophores of other fish and amphibian species. It was found that these iridophores are motile, i.e., these cells respond to certain stimuli with translocation of the platelets within the cells. K+ ions induced dispersion of the platelets in excised scale preparations, but not in excised scales from chemically denervated fish. Norepinephrine and melatonin also induced dispersion of the platelets. Alpha-MSH was effective in aggregating these organelles into the centrospheres of the cells. The conclusions reached are: (1) iridophores of O. obscura are motile; (2) the movement of the iridophores is under nervous and hormonal control. 相似文献
997.
Hideaki Tanaka Tetsuro Yamamoto Yoko Shibuya Norikazu Nishino Sumio Tanase Yoshimasa Miyauchi Takeshi Kambara 《生物化学与生物物理学报:疾病的分子基础》1992,1138(3):243-250
Activation of human plasma prekallikrein by a bacterial metalloendopeptidase, Pseudomonas aeruginosa elastase, was reported (Shibuya et al. (1991) Biochim. Biophys. Acta 1097, 23–27). Details of the activation process were presently studied. The activation accompanied limited proteolysis of a peptide bond inside of a disulfide bridge of prekallikrein molecule. Amino acid sequencing analysis of the newly generated amino-terminal revealed that the cleavage site was Arg371-Ile372 bond which is the scissile bond in the activation of prekallikrein with trypsin-type proteinases. A pentapeptide substrate, 2-aminobenzoyl-Ser-Thr-Ile-Val-4-nitrobenzylamide, which contained the amino acid sequence identical to that around the scissile bond of prekallikrein was synthesized. Pseudomonal elastase, indeed, hydrolyzed the substrate at Arg-Ile bond with the kinetic parameters of Km = 118 μM, kcat = 1.56/s and kcat/Km = 1.33 · 104/s M. These results indicated that the Arg371-Ile372 bond was sensitive not only to trypsin-type serine proteinases, but also a bacterial metalloproteinase. Kinetic analysis of the prekallikrein activation by psuedomonal elastase, however, revealed that the activation rate was show, though the Km values was good enough to expect an occurence of this activation in vivo (Km = 248 nM, k = 6.8 · 10?4/s, and kcat/Km = 2.7 · 103/s M. The activation rate of prekallikrein by pseudomonal elastase in Hageman factor deficient plasma was remarkably improved when the plasma was reconstituted with purified Hageman factor molecule. From the results, a biologuical significance of the proteinase cascade in the plasma kinin generation was also indicated. The present in vitro study might support the hypothesis that the Hageman factor/kallikrein-kinin system plays an important role in bacterial infection including the pseudomonal one. 相似文献
998.
Anti-DNA polymerase a and Ki-67 are monoclonal antibodies that recognize nuclear antigens expressed in proliferating cells. In this study, we evaluated various methods of embedding and fixing brain tumor specimens to optimize staining with these antibodies. In fresh frozen sections, postfixation with 4% paraformaldehyde, 100% methanol, 95% ethanol and 10% buffered formalin were tested; also tested were prefixation with 4% paraformaldehyde followed by freezing and fixation with 100% methanol, 95% ethanol, or 10% buffered formalin followed by embedding in paraffin. For both antibodies, postfixation of fresh frozen sections with 4% paraformaldehyde at 4 C gave the most intense staining and lowest background activity while preserving histological features. This technique can be used in routine clinical practice to predict the growth potential of tumors. 相似文献
999.
Organ distribution of rat kynureninase and changes of its activity during development 总被引:3,自引:0,他引:3
Kynureninase activity was measured in various organs of the rat by a sensitive assay method based on the use of an HPLC system. High activities were detected in liver, kidney and spleen, and much lower activities in adrenals, intestine, lung, heart, brain, skeletal muscle and pancreas. Kynureninase of liver, kidney and spleen showed the same molecular weight (110,000) and the same isoelectric point (pI 5.4). They also showed the same properties of heat stability and apparent optimum pH. The enzymes in kidney and spleen were localized in the cytosol. The developmental study showed increasing activities of the enzyme after birth and a maximum on the 60th day in both liver and spleen. The activity in kidney increased after birth and reached a plateau on the 30th day. 相似文献
1000.
Cloning and sequencing of cDNA that encodes goat growth hormone 总被引:5,自引:0,他引:5
Y Yamano K Oyabayashi M Okuno M Yato N Kioka E Manabe H Hashi H Sakai T Komano K Utsumi 《FEBS letters》1988,228(2):301-304
The cDNA that encodes goat growth hormone (gGH) was isolated from a goat pituitary cDNA library. The cDNA, about 880 base pairs long, had a coding sequence, 5'- and 3'-untranslated regions and a poly(A) chain. The cDNA could encode a polypeptide of 217 amino acids. The amino acid sequence homology between gGH and the sequences of bovine GH, rat GH and human GH was 99, 83 and 66%, respectively. By Northern blot hybridization, we found that the possible gGH gene is transcribed in the goat pituitary. 相似文献