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141.
随着后基因组时代的到来,工业微生物的代谢工程改造在工业生产上发挥着越来越重要的作用。而基因组规模代谢网络模型(Genome-scalemetabolicmodel,GSMM)将生物体体内所有已知代谢信息进行整合,为全局理解生物体的代谢状态、理性指导代谢工程改造提供了最佳的平台。乳酸乳球菌NZ9000(Lactococcuslactis NZ9000)作为工业发酵领域的重要菌株之一,由于其遗传背景清晰且几乎不分泌蛋白,是基因工程改造和外源蛋白表达的理想模式菌株。文中基于基因组功能注释和比较基因组学构建了L.lactisNZ9000的首个基因组规模代谢网络模型iWK557,包含557个基因、668个代谢物、840个反应,并进一步在定性和定量两个层次验证了iWK557的准确性,以期为理性指导L. lactis NZ9000代谢工程改造提供良好工具。 相似文献
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Rui Cheng Xiaoman Zheng Yingmei Wang Xing Ma Xin Liu Wenjun Xu Mengyun Wang Yuanpeng Gao Xupeng Xing Chuan Zhou Hongzheng Sun Zekun Guo Fusheng Quan Jun Liu Song Hua Yongsheng Wang Yong Zhang Xu Liu 《中国科学:生命科学英文版》2022,65(11):2257-2268
Animal cloning can be achieved by somatic cell nuclear transfer(SCNT), but the resulting live birth rate is relatively low. We previously improved the efficiency of bovine SCNT by exogenous melatonin treatment or by overexpression of lysine-specific demethylase 4D(KDM4D) and 4E(KDM4E). In this study, we revealed abundant alternative splicing(AS) transitions during fertilization and embryonic genome activation, and demonstrated abnormal AS in bovine SCNT embryos compared with in vitro fertilized ... 相似文献
144.
Injection of responder mice with poly(Glu60Ala30Tyr10) (GAT) followed by immunization with GAT-methylated bovine serum albumin (GATMBSA) selectively suppresses anti-MBSA plaque-forming cell (PFC) and delayed hypersensitivity (DTH) reactions. Conversely, MBSA injection followed by GATMBSA immunization suppresses anti-GAT PFC and DTH, while anti-MBSA responses remain intact. Suppression occurs for doses of antigen which are optimally immunogenic. The suppression is specific and does not act in a bystander fashion. These results demonstrate that epitope-specific regulation is reciprocal, is not limited to humoral responses, and is not limited to molecules of low molecular weight. 相似文献
145.
W G Wood C Gorka L S Williamson R Strong A Y Sun G Y Sun F Schroeder 《FEBS letters》1986,205(1):25-28
Dolichols are isoprenologues that are found in almost all tissues and whose biochemical function, aside from dolichol phosphate precursors, is not known. In addition, an understanding of the organizational and dynamic properties of dolichols in biological membranes has not been forthcoming. The purpose of the experiments reported here were to examine the effects of dolichol on the physical properties of mouse synaptic plasma membranes (SPM). Differential polarized phase fluorometry indicated that dolichol both fluidized and rigidified SPM. Membrane areas detected by diphenylhexatriene and trans-parinaric acid were selectively fluidized and rigidified, respectively. It also was found that the spin label, 5-doxyl stearic acid indicated that dolichol reduced membrane fluidity. These results report for the first time a structural effect of dolichol on a biological membrane. 相似文献
146.
P Navas I L Sun D J Morré F L Crane 《Biochemical and biophysical research communications》1986,135(1):110-115
The short-term incubation of HeLa cells in the presence of diferric transferrin or ferricyanide, which are reduced externally by the transplasma membrane reductase, produces a stoichiometric decrease in NADH and increase in NAD+, which is stimulated by insulin. The NADP/NADPH ratio does not change during 15 min incubation with the oxidants. The total pyridine nucleotide pool of HeLa cells is not affected. Incubation with apotransferrin and ferrocyanide, which cannot act as oxidants for transmembrane electron transport, does not change the pyridine nucleotide concentrations in the cells. Our results show that NADH can act as the internal electron donor for the reduction of external oxidants by the transmembrane reductase. It appears that oxidation of NADH by the transmembrane electron transport using ferricyanide or iron transferrin as external electron acceptors is sufficient to stimulate growth in HeLa cells. 相似文献
147.
I L Sun R Garcia-Ca?ero W Liu W Toole-Simms F L Crane D J Morré H L?w 《Biochemical and biophysical research communications》1987,145(1):467-473
Proton release from HeLa cells is stimulated by external oxidants for the transplasmalemma electron transport enzymes. These oxidants, such as ferricyanide and diferric transferrin, also stimulate cell growth. We now present evidence that proton release associated with the reduction of ferricyanide and diferric transferrin is through the Na+/H+ antiport. The stoichiometry of H+/e- release with diferric transferrin is over 50 to 1, which is greater than expected for oxidation of a protonated transmembrane electron carrier. Diferric transferrin induced proton release depends on external sodium and is inhibited by amiloride. Proton release is also inhibited when diferric transferrin reduction is inhibited by apotransferrin. A tightly coupled association between the redox system and the antiport is shown by sodium dependence and amiloride inhibition of diferric transferrin reduction. The results indicate a new role for ferric transferrin in growth stimulation by activation of the sodium-proton antiport. 相似文献
148.
Chang Ge Huakang Sheng Xin Chen Xiaolin Shen Xinxiao Sun Yajun Yan Jia Wang Qipeng Yuan 《Biotechnology journal》2020,15(6)
Quorum sensing (QS) is a ubiquitous cell–cell communication mechanism in microbes that coordinates population‐level cell behaviors, such as biofilm production, virulence, swarming motility, and bacterial persistence. Efforts to engineer QS systems to take part in metabolic network regulation represent a promising strategy for synthetic biology and pathway engineering. Recently, design, construction, and implementation of QS circuits for programmed control of bacterial phenotypes and metabolic pathways have gained much attention, but have not been reviewed recently. In this article, the architectural organizations and genetic contributions of the naturally occurring QS components to understand the mechanisms are summarized. Then, the most recent progress in application of QS toolkits to develop synthetic networks for novel cell behaviors creation and metabolic pathway engineering is highlighted. The current challenges in large‐scale application of these QS circuits in synthetic biology and metabolic engineering fields are discussed and future perspectives for further engineering efforts are provided. 相似文献
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MiR‐616‐3p modulates cell proliferation and migration through targeting tissue factor pathway inhibitor 2 in preeclampsia 下载免费PDF全文
Yetao Xu Dan Wu Ziyan Jiang Yuanyuan Zhang Sailan Wang Zhonghua Ma Bingqing Hui Jing Wang Weiping Qian Zhiping Ge Lizhou Sun 《Cell proliferation》2018,51(5)