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糖生物学--破解基因组功能的必由之路 总被引：9，自引：0，他引：9
金城 《中国科学院研究生院学报》2001,18(1):66-45
介绍了糖生物学研究的意义和动态,包括糖链与糖结合蛋白识别介导的细胞黏附,糖链在新生肽链折叠过程中、在免疫系统中、在细胞信号传导中的作用,糖链与微生物感染、糖链代谢疾病、糖链的化学合成与分析,以及糖生物学研究的特点和发展趋势. 相似文献
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毕赤酵母具有原核生物易于培养、繁殖快、便于基因工程操作和高密度发酵等特性,同时又具有真核生物中蛋白正确折叠所需的细胞内环境和糖链加工系统,还能将外源蛋白分泌到培养液中,利于纯化,因此,毕赤巴斯德酵母成为近年来发展最为迅速,应用也最为广泛的外源基因表达系统。本文主要介绍了毕赤酵母常见表达载体,提高表达量的对策,以及该表达系统在基因工程抗体方面的一些应用现状。 相似文献
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利用同源克隆的方法,从商陆中克隆得到扩展蛋白基因的全长cDNA序列,命名为PaEXP1(GenBank 登录号为GQ851947).PaEXP1长1128bp,含有759bp的完整开放阅读框,编码252个氨基酸,分子量27.1kD,等电点8.55.PaEXP1氨基酸序列N端含有8个半胱氨酸残基,1个组氨酸(His-Phe-Asp,HFD)域,C末端存在4个保守的色氨酸残基,具有扩展蛋白的典型结构.系统进化树分析表明,PaEXP1属于扩展蛋白的α-扩展蛋白家族.Real time-PCR结果表明,PaEXP1主要在根中表达,低温、盐、重金属和渗透胁迫均强烈地抑制其基因的表达.酵母转化实验表明,转PaEXP1可以提高酵母的平均直径,说明PaEXP1参与细胞壁的松弛扩展和细胞的增大过程. 相似文献
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《科技风》2021,(15)
目的:探究microRNA-369-5p(miR-369-5p)在糖尿病心肌病心肌组织与心肌成纤维细胞(cardiac fibroblasts CFs)活化增殖中的表达变化。方法:通过腹腔注射链脲佐菌素(STZ)构建大鼠糖尿病心肌病模型,体外应用高糖诱导CFs细胞活化增殖模型。利用HE、Masson染色,观察心肌组织病理改变及胶原分布情况。应用qRT-PCR检测CFs细胞中miR-369-5p的表达。qRT-PCR和Western blotting实验检测α-SMA、Collagen I mRNA与蛋白的表达;结果:HE和Masson染色显示糖尿病心肌病大鼠心肌胶原沉积明显增多,细胞相对排列紊乱,细胞大小不一。Western blotting实验表明与正常组相比,糖尿病组和高糖组的α-SMA与Collagen I的表达增长;qRT-PCR实验表明与正常组相比,高糖诱导CFs细胞中miR-369-5p表达降低,而α-SMA与Collagen I的表达增加。结论:miR-369-5p在糖尿病心肌病心肌组织与高糖诱导CFs细胞中表达降低,提示miR-369-5p可能是影响糖尿病心肌病形成的潜在作用靶点。 相似文献
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酒曲微生物成分对青稞酒品质的影响研究 总被引：1，自引：0，他引：1
培养取自拉萨市墨竹贡卡县、拉萨市尼木县、日喀则地区江孜县、山南地区浪卡子县、昌都地区芒康县等五个地区酒曲.分离鉴定出青稞酒酒曲中的主要微生物为毛霉、根霉和酵母.利用五种酒曲分别发酵青稞酒,分析各处理青稞酒的旋光度、酒精度、PH值等指标以及感官指标的差异,初步确定分离出的微生物对青稞酒品质的影响.最后选墨竹贡卡的酒曲用不同浓度梯度的青稞酒酒曲中的微生物发酵青稞酒,初步确定根霉可以明显降低青稞酒的酸度,酵母的加入能有效提高青稞酒的酸度,毛霉对于青稞酒糖度和酒精度均有明显提高作用. 相似文献
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低温胁迫对不同扁蓿豆种子内游离脯氨酸和可溶性糖含量的影响 总被引：1，自引：0，他引：1
在低温胁迫（-4℃）及不同时间长度（24h、48h、72h）下,以扁蓿豆种子（青藏扁蓿豆、内蒙古直立型扁蓿豆、青海匍匐型扁蓿豆、盐池扁蓿豆和吉林扁蓿豆）5个样品为材料,研究了扁蓿豆种子内游离脯氨酸和可溶性糖含量的变化规律。结果表明：在低温胁迫下,5个品种扁蓿豆种子内游离脯氨酸和可溶性糖的绝对含量都是呈现出上升的趋势,从而证明扁蓿豆种子是通过提高游离脯氨酸和可溶性糖的绝对含量来适应低温逆境、减轻低温伤害的,也进一步证明游离脯氨酸和可溶性糖可作为植物抗寒性的一项生理生化指标。 相似文献
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刘秀贵 《中国科学院研究生院学报》2005,22(1):11-18
证明在Adams谱序列中,积b0h1γs∈Exts+3,A
sp2 q+(s+1)pq+(s-2)q+(s-3)(Zp,Zp)收敛到球面稳定同伦群π*S中的一个新的非零的稳定元素族,其中3≤s＜p,p≥7为奇素数. 相似文献
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从垂序商陆(Phytolacca americana)的重金属镉胁迫下商陆幼苗叶片的正反向抑制性消减杂交文库(SSH文库)中,获得商陆寡肽转运蛋白基因的EST序列.利用RACE的方法克隆到该基因的全序列cDNA(PaOPT,GenBank注册HQ647015).PaOPT基因在进化中的地位分析表明:它可能属于OPT3基因家族.利用实时荧光定量PCR的方法,分析PaOPT的组织表达特异性以及商陆种子成熟及萌发过程的表达模式.结果表明,该基因是一个在种子中特异性表达的基因,预测它对植物的生长发育有着重要的作用. 相似文献
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BackgroundIn industrial yeasts, selection and breeding for resistance to multiple stresses is a focus of current research. The objective of this study was to investigate the tolerance to multiple stresses of Saccharomyces cerevisiae obtained through an adaptive laboratory evolution strategy involving a repeated liquid nitrogen freeze–thaw process coupled with multi-stress shock selection. We also assessed the related resistance mechanisms and very high-gravity (VHG) bioethanol production of this strain.ResultsElite S. cerevisiae strain YF10-5, exhibiting improved VHG fermentation capacity and stress resistance to osmotic pressure and ethanol, was isolated following ten consecutive rounds of liquid nitrogen freeze–thaw treatment followed by plate screening under osmotic and ethanol stress. The ethanol yield of YF10-5 was 16% higher than that of the parent strain during 35% (w/v) glucose fermentation. Furthermore, there was upregulation of three genes (HSP26, HSP30, and HSP104) encoding heat-shock proteins involved in the stress response, one gene (TPS1) involved in the synthesis of trehalose, and three genes (ADH1, HXK1, and PFK1) involved in ethanol metabolism and intracellular trehalose accumulation in YF10-5 yeast cells, indicating increased stress tolerance and fermentative capacity. YF10-5 also showed excellent fermentation performance during the simultaneous saccharification and fermentation of VHG sweet potato mash, producing 13.40% (w/v) ethanol, which corresponded to 93.95% of the theoretical ethanol yield.ConclusionsA multiple-stress-tolerant yeast clone was obtained using adaptive evolution by a freeze–thaw method coupled with stress shock selection. The selected robust yeast strain exhibits potential for bioethanol production through VHG fermentation.How to cite: Zhang Q, Jin Y, Fang Y, et al. Adaptive evolution and selection of stress-resistant Saccharomyces cerevisiae for very high gravity bioethanol fermentation. Electron J Biotechnol 2019;41. https://doi.org/10.1016/j.ejbt.2019.06.003 相似文献
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《Electronic Journal of Biotechnology》2014,17(6):262-267
BackgroundThe Tibetan pig is a pig breed with excellent grazing characteristics indigenous to the Qinghai–Tibet plateau in China. Under conditions of barn feeding, 90% of its diet consists of forage grass, which helps meet its nutritional needs. The present study aimed to isolate and identify a cellulolytic bacterium from the Tibetan pig's intestine and investigate cellulase production by this bacterium. The study purpose is to provide a basic theory for the research and development of herbivore characteristics and to identify a source of probiotics from the Tibetan pig.ResultsA cellulolytic bacterium was isolated from a Tibetan pig's intestine and identified based on morphological, physiological, and biochemical characteristics as well as 16S rRNA analysis; it was designated Bacillus subtilis BY-2. Examination of its growth characteristics showed that its growth curve entered the logarithmic phase after 8–12 h and the stable growth phase being between 20 and 40 h. The best carbon source for fermentation was 1% corn flour, while 2% peptone and yeast powder compound were the best nitrogen sources. The initial pH during fermentation was 5.5, with 4% inoculum, resulting in a high and stable amount of enzyme in 24–48 h.ConclusionsThe isolated BY-2 strain rapidly grew and produced cellulase. We believe that BY-2 cellulase can help overcome the shortage of endogenous animal cellulase, improve the utilization rate of roughage, and provide strain sources for research on porcine probiotics. 相似文献
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我校学报论文的引文统计分析 总被引：11，自引：1，他引：10
本文用文献计量学的方法,对《南京农业大学学报》1992-1997年发表的论文及其引文进行了统计分析。结果表明：6年共发表论文602篇,平均每期25.1篇;共有作者1767人（次）,平均每篇约2.9人;论文发表的平均时差为11个月;有594篇论文附有引文;平均引文量为7.6篇,无引率为1.3%;引文语种：中文占51.6%,英文占47.7%;引文类型：期刊占71.6%,图书和特种文献分别占23%和5.4%;中外文农业文献的半衰期分别为7.70年和14.20的;引用次数最多的中文期刊为要本校学报;中外文最大引有年限分别为3年和9年。 相似文献
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热带假丝酵母（Candida tropicalis）是长碳链二元酸发酵生产中的常用菌种，而热带假丝酵母突变株HP-2-48是一株高产DC12的优良生产菌株。本文对十二碳二元酸的发酵进行了研究，考察了青霉素钠盐、尿素、丙烯酸、pH值对菌体生长、产酸的影响并对其作用机制进行了讨论，并据此建立了长碳链二元酸新的发酵工艺。 相似文献
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Pragna Rao Anuradha Kumar N. R. Rau T. N. Pattabiraman 《Indian journal of clinical biochemistry : IJCB》1990,5(2):117-122
In persons with impaired glucose tolerance, serum glycated proteins (9.44±1.46μg hexose/mg protein) increased 1.69-fold (P<0.001)
over control subjects compared to an increase of 1.95-fold in overt diabetics. However, correlations between serum glycated
protein values and 2 h blood sugar values during the tolerance test (r=0.39) and between the former and graph area (r=0.30)
were not strong. Glycated albumin (2.25 mol hexose/mol protein) and glycated haemoglobin (0.398±0.07 mol hexose/mol protein)
in the study group also showed 1.67 and 1.24-fold increase respectively compared to controls. Fairly good correlations between
glycated serum protein and glycated albumin (r=0.50) and glycated haemoglobin (r=0.45) were observed during this study. The
data suggest that measurement of glycated proteins will be a useful index to detect impaired glucose tolerance. 相似文献
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Praveen Kumar Shetty T. N. Pattabiraman 《Indian journal of clinical biochemistry : IJCB》2004,19(1):97-101
The present study deals with the estimation of total carbohydrate, protein bound carbohydrate, bound fucose and sialic acid
along with total protein in disease conditions like gingivitis, periodontitis and their comparison with the normals.
The neutral hexose values in gingivitis (8.08±2.20mg/100mg protein) and periodontitis (12.5±2.16mg/ 100mg protein) decreased
significantly when expressed per 100 mg protein compared to normals (19.8±1.89mg/100mg protein). This might be because of
higher protein concentration in these two clinical conditions. The ethanol insoluble hexose values were significantly reduced
in both these conditions compared to controls (3.71±1.64,5.91±1.63,7.65±0.86mg/100mg protein respectively). The ethanol soluble
hexose values were also found to be drastically reduced. This decrease in saliva appears to be characteristic feature of oral
diseases. In gingivitis and periodontitis fucose level was found to be increased compared to normals when expressed as a function
of salivary volume. However in terms of protein concentration the values in gingivitis (2.95±1.59), periodontitis (3.26±0.98)
and normals (3.20±0.50mg/100mg) were not different. Sialic acid in ethanol insoluble fraction of salivary samples mg/100mg
protein was found to be significantly reduced in both gingivitis (0.78±0.33) and periodontitis (0.95±0.31) compared to controls
(1.92±0.33) 相似文献