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101.
Abstract: A new protein kinase modulated by S-100 (tentatively referred to as protein kinase X) was partially purified from pig brain extracts. The activity of protein kinase X, which was independent of Ca2+ , was demonstrated when protamine (free base), but not protamine sulfate and other proteins (including histone), was used as substrate. The enzyme activity, found to distribute in both soluble and particulate fractions and to occur at the highest level in brain compared with other tissues (heart, kidney, liver, skeletal muscle, spleen, and testis) of rats, was also modulated by other acidic proteins (calmodulin, troponin C, and stimulatory modulator) in a Ca2+ -independent manner. S-100 and other acidic proteins appeared to function as "substrate modifiers" by interacting with protamine (a highly basic protein), but not with the enzyme, thus rendering protamine in the complex a superior phosphate acceptor. The two isoforms of S-100 (i.e., a and b) were equally effective. Although the enzyme was not inhibited by many agents (trifluoperazine, melittin, cytotoxin I, polymyxin B, and spermine) shown to inhibit markedly phospholipid/Ca2+ - or calmodulin/Ca2+ -stimulated protein kinase, gossypol was found to inhibit specifically protein kinase X. The present findings suggest that S-100, a major acidic protein specific to nervous system, may promote phosphorylation by protein kinase X of certain neural proteins resembling protamine or containing protamine-like domains, in addition to its presumed role of a low-affinity Ca2+ -binding protein. 相似文献
102.
Kanefusa Kato Fujiko Suzuki Rika Morishita Tomiko Asano Tsuneko Sato 《Journal of neurochemistry》1990,54(4):1269-1274
Changes in the concentrations of nervous tissue-related proteins and their isoproteins, such as S-100 proteins (S-100 alpha and S-100 beta), enolase isozymes (alpha-enolase and gamma-enolase), and GTP-binding proteins (Go alpha, Gi2 alpha, and beta-subunits), were determined in the CNS of male rats of various ages (from 2 to 30 months old) by means of enzyme immunoassay. The weights of brains and the concentrations of soluble proteins in the cerebral cortex, cerebellum, and brainstem were constant during the observation period. The concentration of S-100 beta protein, which is predominantly localized in glial cells, increased gradually in the cerebral cortex with age; levels in the 25-month-old rats increased to approximately 150% of the levels in the young (2-month-old) rats. However, the S-100 beta concentrations in the cerebellum and brainstem were relatively constant, showing similar values in rats 2-30 months old. Levels of other proteins, including both neuronal (gamma-enolase and Go alpha) and glial (alpha-enolase and S-100 alpha) marker proteins, did not change significantly with age in the cerebral cortex, cerebellum, and brainstem. These results suggest that there is a close relation between the age-dependent changes of the CNS function and S-100 beta protein levels in the cerebral cortex. 相似文献
103.
探讨血清MCP-1、VE-cadherin和S-100蛋白水平变化对脑梗死患者病情的影响。选择2016年3月至2017年5月期间我院确诊的脑梗死患者60例作为研究对象,男性30例,女性30例,平均年龄为(60.2±8.1)岁。选择同期在我院进行体检的30名健康志愿者作为对照组。采用酶联免疫双抗体夹心法检测受试者血清MCP-1、VE-cadherin和S-100蛋白水平。脑梗死患者的血清MCP-1、VE-cadherin和S-100水平均高于对照组(p<0.05)。进展性脑梗死患者血清MCP-1、VE-cadherin和S-100水平显著升高(p<0.05)。轻型神经功能缺损患者的血清MCP-1、VE-cadherin和S-100水平显著低于中型和重型患者(p<0.05),中型患者血清MCP-1、VE-cadherin和S-100水平均显著低于重型患者(p<0.05)。脑梗死患者的血清MCP-1、VE-cadherin和S-100参与脑梗死的发生发展,并且与脑梗死患者的临床表现和神经功能缺损程度有关。 相似文献
104.
A glyphosate (N-[phosphonomethyl]glycine)-insensitive 5-enolpyruvylshikimic acid-3-phosphate (EPSP) synthase has been purified from a strain of Klebsiella pneumoniae which is resistant to this herbicide [(1984) Arch. Microbiol. 137, 121-123] and its properties compared with those of the glyphosate-sensitive EPSP synthase of the parent strain. The apparent Km values of the insensitive enzyme for phosphoenolpyruvate (PEP) and shikimate 3-phosphate (S-3-P) were increased 15.6- and 4.3-fold, respectively, as compared to those of the sensitive enzyme, and significant differences were found for the optimal pH and temperature, as well as the isoelectric points of the two enzymes. While PEP protected both enzymes against inactivation by N-ethylmaleimide, 3-bromopyruvate, and phenylglyoxal, glyphosate protected only the sensitive enzyme. 相似文献
105.
Immunocytochemical localization of S-100 protein in astrocytes and Müller cells in the rabbit retina
Jutta Schnitzer 《Cell and tissue research》1987,248(1):55-61
Summary The localization of S-100 protein was studied in histological sections of retinae from adult rabbits. By use of double-immunolabeling techniques it was shown that most but not all radially oriented vimentin-positive Müller cells were co-labeled by an antiserum to S-100 protein. Glial fibrillary acidic protein-positive astrocytes, which in the rabbit retina are restricted to the medullary rays formed by myelinated optic nerve fibers, consistently showed S-100 protein immunoreactivity. The present report shows that, with respect to S-100 protein staining, Müller cells represent a heterogeneous population of glial elements. 相似文献
106.
目的:探讨脑脊液降钙素原(PCT)、血管内皮生长因子(VEGF)、S100B蛋白(S-100B)、神经元特异性烯醇化酶(NSE)、基质金属蛋白酶(MMP)及降钙素基因相关肽(CGRP)水平联合检测在病毒性脑炎患儿中的诊断价值和意义。方法:选取2012年6月至2014年6月收治的病毒性脑炎患儿106例作为研究组,选取同时期来我院进行健康体检的60例儿童作为对照组,比较两组脑脊液PCT、VEGF、S-100B、NSE、MMP及CGRP水平,并分析研究组依照不同层次分组后以上各指标的差异。结果:研究组脑脊液中PCT、VEGF、S-100B、NSE、MMP及CGRP水平明显高于对照组,差异具有统计学意义(P0.05);研究组重症患儿高于轻症患者,急性期患者高于非急性期患儿,差异均具有统计学意义(P0.05)。以上各指标中任意二种、三种、四种及五种联合检测,其诊断效能均在0.923-0.967之间,六种指标联合检测的效能最高为0.975。结论:病毒性脑膜炎患儿血清及脑脊液PCT、VEGF、S-100B、NSE、MMP及CGRP水平均呈现升高的趋势,且不同严重程度及分期患儿的以上指标均有一定的差异,六种指标联合检测诊断病毒性脑炎患儿的效能最高。 相似文献
107.
Microtubules and the organization of the Golgi complex 总被引:42,自引:0,他引:42
Electron microscopic and cytochemical studies indicate that microtubules play an important role in the organization of the Golgi complex in mammalian cells. During interphase microtubules form a radiating pattern in the cytoplasm, originating from the pericentriolar region (microtubule-organizing centre). The stacks of Golgi cisternae and the associated secretory vesicles and lysosomes are arranged in a circumscribed juxtanuclear area, usually centered around the centrioles, and show a defined orientation in relation to the rough endoplasmic reticulum. Exposure of cells to drugs such as colchicine, vinblastine and nocodazole leads to disassembly of microtubules and disorganization of the Golgi complex, most typically a dispersion of its stacks of cisternae throughout the cytoplasm. These alterations are accompanied by disturbances in the intracellular transport, processing and release of secretory products as well as inhibition of endocytosis. The observations suggest that microtubules are partly responsible for the maintenance and functioning of the Golgi complex, possibly by arranging its stacks of cisternae three-dimensionally within the cell and in relation to other organelles and ensuring a normal flow of material into and away from them. During mitosis, microtubules disassemble (prophase) and a mitotic spindle is built up (metaphase) to take care of the subsequent separation of the chromosomes (anaphase). The breaking up of the microtubular cytoskeleton is followed by vesiculation of the rough endoplasmic reticulum and partial atrophy, as well as dispersion of the stacks of Golgi cisternae. After completion of the nuclear division (telophase), the radiating microtubule pattern is re-established and the rough endoplasmic reticulum and the Golgi complex resume their normal interphase structure. This sequence of events is believed to fulfil the double function to provide tubulin units and space for construction of the mitotic spindle and to guarantee an approximately equal distribution of the rough endoplasmic reticulum and the Golgi complex on the two daughter cells. 相似文献
108.
江汉平原及其周边地区花生根瘤菌的遗传多样性 总被引:12,自引:3,他引:12
采用RAPD分析技术和16S-23S rRNA间隔区段(IGS)RFLP分析,分别对分离自江汉平原及其周缘地区的花生根瘤菌进行了遗传多样性和系统发育研究。结果表明,全部供试验菌分别在48%和50%的相似性水平分为Ⅰ、Ⅱ两群,供试花生根瘤菌与参比菌株B.japonicum和B.elkanii聚在群I,参比菌株Rhizobium Sinorhizobium,Mesorhizobium和Agrobacterium聚在群Ⅱ。供试花生根瘤菌的遗传多样性及其在系统发育中的地位主要受地域因素的影响,来自江汉平原中心地带天门和潜江的菌株在76%以上的相似性水平上聚在一起,处于周边地带的武汉和荆州,由于其特定的地理因素的影响。菌株的多样性更为丰富,部分菌株在分类上与其它地域的菌株相互融合,并在较高的相似水平存在一定摆动性,来自外缘随州的菌株,表现了明显的地理分隔作用,其在系统演化中的地位相对独立,总体上从平原腹地到外缘地区。根瘤菌地理分隔作用逐渐明显,在平原外缘的交接地带,根瘤菌的多样性最为丰富。 相似文献
109.
M. Ferchichi R. Valcheva N. Oheix P. Kabadjova H. Prévost B. Onno X. Dousset 《World journal of microbiology & biotechnology》2008,24(11):2425-2434
The aim of the present research is to identify rapidly the lactic acid bacteria (LAB) microflora of four natural French sourdoughs
(GO, BF, VB and RF), applying a biphasic (restriction length polymorphism (RFLP) and sequencing) approach for bacterial identification.
For this purpose, a database with the RFLP patterns of 30 lactobacilli type strains was created. So-developed ISR-RFLP algorithm
was further applied for the differentiation and identification of 134 sourdough isolates. The 16S-23S rDNA intergenic spacer
region was amplified by primers tAla and 23S/10, and then digested by HindIII, HinfI and α-TaqI enzymes. Nucleotide sequences of the cloned 16S-23S intergenic spacer region (ISR) were determined by the dideoxynucleotide
chain termination method. The T7Prom and M13rev primers flanking the multiple cloning site of pCR2.1 DNA were used to sequence
both DNA strands. The RFLP profile obtained upon digestion with HindIII, HinfI and α-TaqI enzymes can be used to discriminate Lactobacillus sanfranciscensis (66%), Lactobacillus
panis (17%), Lactobacillus nantensis (11%) and Lactobacillus hammesii(6%) in sourdough GO, Lactobacillus sanfranciscensis (80%), Lactobacillus spicheri (14%) and Lactobacillus pontis(6%) in sourdoughs BF. In sourdoughs VB, which differed in the process temperature, we can differentiate Lactobacillus sanfranciscensis (89%) and Leuconostoc mesenteroidessubsp. mesenteroides (11%). Lactobacillus frumenti(47%), Lactobacillus hammesii (8%), and Lactobacillus paralimentarius (45%) were differentiated in sourdough RF. 相似文献
110.
Nomeda Kuisiene Juozas Raugalas Donaldas Chitavichius 《Central European Journal of Biology》2008,3(4):396-406
The aim of this study was to evaluate the inter-and intraspecific as well as intragenomic variability of Geobacillus 16S–23S rRNA internal transcribed spacers without tRNA genes and to compare these sequences with sequences bearing tRNA genes.
In this study the structural analysis was performed in a unique way because the length and the sequence of the structural
blocks were adjusted to fit the structure of 16S–23S rRNA internal transcribed spacers of five different Geobacillus species. Our study demonstrated the mosaic-like structure of 16S–23S rRNA internal transcribed spacers in Geobacillus. Some characteristics of these spacers of geobacilli were not previously reported for other bacteria: unusually short conserved
sequence in the 5′ end region, some identical conserved blocks in both 5′ and 3′ regions of 16S–23S rRNA internal transcribed
spacers, the same sequence blocks in both 16S–23S and 23S–5S rRNA intergenic spacers. Our study demonstrated quite uniform
arrangement of the sequence blocks in Geobacillus thermodenitrificans. This species diverged early in the phylogenetic tree of the genus Geobacillus. For the phylogenetically recent species Geobacillus kaustophilus and Geobacillus lituanicus the low inter-and intraspecific, but high intragenomic variability, as a consequence of recent phylogenetic events, was established. 相似文献