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871.
Dong Tu Nguyen Tuan Cuong Ngo Huy Hoang Tran Thi Phuong Lan Nguyen Binh Minh Nguyen Kouichi Morita & Masahiko Ehara 《FEMS microbiology letters》2009,298(1):37-43
Autoagglutinable strains of Vibrio cholerae O1 (seven nonfimbriate strains and one fimbriate strain) were transformed to obtain resistance to ampicillin. Two distinct mechanisms were found in these strains. One was operating in nonfimbriate strains by reducing OmpU protein production and the other was operating in a fimbriate strain (Bgd17) by newly overproducing cpxP protein. The twitching motility in the fimbriate Bgd17 strain disappeared depending on the production of cpxP protein, suggesting that fimbriation of V. cholerae O1 is controlled by a two-component signal transduction system. 相似文献
872.
Renal cytosolic extracts from rats of different ages and mononephrectomized rats were incubated with gamma-[32P]ATP and analysed by high resolution two-dimensional electrophoresis and autoradiography. Extracts from new-born and young rats showed a great number of phosphorylated proteins migrating between the origin and Mr 52,000. Among these proteins, the group co-migrating with phosphorylase b (Mr 97,000) was particularly evident in new-born and days-old rats. In extracts from mature rats, other proteins of lower molecular weight, particularly those migrating between Mr 60,000 and 44,000, became intensely phosphorylated. The number and intensity of phosphorylated proteins from extracts of normal and nephrectomized rats, however, did not vary. Activity of cAMP-dependent protein kinase and [3H]cAMP binding was also modified during neonatal development but not in compensatory renal growth. Since cAMP-PK and protein phosphorylation are known to be regulated in response to hormonal stimulations, these results may provide good indications for the understanding of hormonal involvement in kidney growth. 相似文献
873.
Son Hoang Minh Duc Hoang Minh Masuda Yoshimitsu Honjoh Ken-ichi Miyamoto Takahisa 《Applied microbiology and biotechnology》2018,102(23):10259-10271
Applied Microbiology and Biotechnology - Shiga toxin-producing Escherichia coli (STEC) O157:H7 and extended-spectrum beta-lactamase (ESBL) producing E. coli (ESBLEC) are important bacteria of... 相似文献
874.
Duc Hoang Bingyu Kuang George Liang Zhao Wang Seongkyu Yoon 《Biotechnology progress》2023,39(2):e3313
Therapeutic protein productivity and glycosylation pattern highly rely on cell metabolism. Cell culture medium composition and feeding strategy are critical to regulate cell metabolism. In this study, the relationship between toxic metabolic inhibitors and their nutrient precursors was explored to identify the critical medium components toward cell growth and generation of metabolic by-products. Generic CHO metabolic model was tailored and integrated with CHO fed-batch metabolomic data to obtain a cell line- and process-specific model. Flux balance analysis study was conducted on toxic metabolites cytidine monophosphate, guanosine monophosphate and n-acetylputrescine—all of which were previously reported to generate from endogenous cell metabolism—by mapping them to a compartmentalized carbon utilization network. Using this approach, the study projected high level of inhibitory metabolites accumulation when comparing three industrially relevant fed-batch feeding conditions one against another, from which the results were validated via a dose-dependent amino acids spiking study. In the end, a medium optimization design was employed to lower the amount of supplemented nutrients, of which improvements in critical process performance were realized at 40% increase in peak viable cell density (VCD), 15% increase in integral VCD, and 37% increase in growth rate. Tight control of toxic by-products was also achieved, as the study measured decreased inhibitory metabolites accumulation across all conditions. Overall, the study successfully presented a digital twin approach to investigate the intertwined relationship between supplemented medium constituents and downstream toxic metabolites generated through host cell metabolism, further elucidating different control strategies capable of improving cellular phenotypes and regulating toxic inhibitors. 相似文献
875.
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877.
Tanja Sigl Gregor Schlamberger Hermine Kienberger Steffi Wiedemann Heinrich HD Meyer Martin Kaske 《Acta veterinaria Scandinavica》2010,52(1):32
Background
Conjugated linoleic acid (CLA) is a collective term for isomers of octadecadienoic acid with conjugated double-bond system. Thus, it was the objective to investigate whether milk composition and metabolic key parameters are affected by adding CLA to the diet of dairy cows in the first four weeks of lactation. 相似文献878.
Hung Le Dinh Nguyen Hoang Thi Trang Trang Vo Thi Dieu 《Journal of applied phycology》2021,33(3):1819-1824
Journal of Applied Phycology - The red alga Kappaphycus striatus “sacol” brown strain is an economically important species and extensively cultivated at Vanphong Bay, Vietnam. To... 相似文献
879.
Zhexi Chi Truc Phan Hoang Le Sang Ki Lee Erling Guo Dongsoo Kim Sanha Lee Seung‐Yong Seo Sook Young Lee Jae Hyung Kim Sang Yoon Lee 《Journal of cellular and molecular medicine》2020,24(18):10663-10676
Hypertension and endothelial dysfunction are associated with various cardiovascular diseases. Hydrogen sulphide (H2S) produced by cystathionine γ‐lyase (CSE) promotes vascular relaxation and lowers hypertension. Honokiol (HNK), a natural compound in the Magnolia plant, has been shown to retain multifunctional properties such as anti‐oxidative and anti‐inflammatory activities. However, a potential role of HNK in regulating CSE and hypertension remains largely unknown. Here, we aimed to demonstrate that HNK co‐treatment attenuated the vasoconstriction, hypertension and H2S reduction caused by angiotensin II (AngII), a well‐established inducer of hypertension. We previously found that histone deacetylase 6 (HDAC6) mediates AngII‐induced deacetylation of CSE, which facilitates its ubiquitination and proteasomal degradation. Our current results indicated that HNK increased endothelial CSE protein levels by enhancing its stability in a sirtuin‐3‐independent manner. Notably, HNK could increase CSE acetylation levels by inhibiting HDAC6 catalytic activity, thereby blocking the AngII‐induced degradative ubiquitination of CSE. CSE acetylation and ubiquitination occurred mainly on the lysine 73 (K73) residue. Conversely, its mutant (K73R) was resistant to both acetylation and ubiquitination, exhibiting higher protein stability than that of wild‐type CSE. Collectively, our findings suggested that HNK treatment protects CSE against HDAC6‐mediated degradation and may constitute an alternative for preventing endothelial dysfunction and hypertensive disorders. 相似文献
880.
The Pseudomonas aeruginosa leuB gene, encoding 3-isopropylmalate dehydrogenase, was identified upstream of asd, encoding aspartate-β-semialdehyde dehydrogenase. Genetic analysis indicated that leuB is identical to the previously mapped gene defined by the leu-10 allele. The chromosomal leuB locus was inactivated by gene replacement. The insertions had no adverse effect on expression of the downstream asd gene but resulted in leucine auxotrophy. The leuB gene encodes a protein containing 360 amino acids (with a molecular weight of 39153), which was expressed in Escherichia coli as a M, 42000 protein. The results suggested that, in contrast to the situation in other bacteria (E. coli, Salmonella typhimurium and Bacillus subtilis) the P. aeruginosa leuB gene is physically separated from the genes encoding the other enzymes of the isopropylmalate pathway.
Received: 15 August 1996 / Accepted: 23 October 1996 相似文献