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71.
We have used specific oligonucleotide probes to measure the effect of hydralazine on mRNA levels of the alpha and beta subunits of prolyl 4-hydroxylase (PH), a key post-translational modifying enzyme in collagen biosynthesis. Hydralazine exerts a paradoxical effect on collagen biosynthesis in cultured fibroblasts. Cells exposed to hydralazine synthesize substantially reduced amounts of collagen, which is severely deficient in hydroxyproline. Surprisingly, however, the level of prolyl hydroxylase activity assayed in extracts of treated cells is markedly increased, suggesting overproduction of the enzyme. Hybridization analysis indicated that in untreated cells the concentration of the alpha PH subunit mRNA was about 20-25% of the beta PH subunit mRNA concentration. Hydralazine treatment increased the mRNAs for both alpha and beta subunits of PH by three- to fourfold. A differential induction of these mRNAs was observed, however. The alpha subunit mRNA was maximally increased within 24 h, whereas the beta subunit mRNA was increased more slowly, reaching a maximum at 72 h. In contrast, the 5.8 and 4.8-kb mRNAs for pro alpha 1(I) collagen were virtually eliminated by 72 h. This study demonstrates that the increased prolyl hydroxylase activity is a direct result of hydralazine-mediated increases in steady state mRNA content for the alpha and beta subunits of this enzyme. Moreover, the earlier induction of alpha PH mRNA may provide the first evidence at the mRNA level that regulation of PH activity occurs mainly through regulation of the alpha subunit of PH. In addition, the decrease in collagen synthesis by hydralazine appears to result directly from suppression of both species of mRNA for pro alpha 1(I) collagen. 相似文献
72.
Biosurfactant production and use in oil tank clean-up 总被引:6,自引:0,他引:6
I. M. Banat N. Samarah M. Murad R. Horne S. Banerjee 《World journal of microbiology & biotechnology》1991,7(1):80-88
A proprietary bacterial strain (Pet 1006) produced biosurfactants when grown on both glucose and an immiscible hydrocarbon as carbon sources. Pilot-plant-scale (1500 I) production gave, on repeated batch runs, 2 tonnes of culture broth containing active biosurfactant. The product was used as a substitute for chemical surfactants in a clean-up demonstration test carried out by Cargo Fleet Chemical Company Ltd. (UK) on an oil storage tank belonging to Kuwait Oil Company, Kuwait. The clean-up was successful in removing the sludge from the tank bottom, and it also allowed the recovery of more than 90% of the hydrocarbon trapped in the sludge. The recovered hydrocarbon had excellent properties and could be sold after being blended with fresh crude.I.M. Banat is at 5, Upper Galliagh Road, Londonderry, Northern Ireland BT48 8LW, UK but was at the Kuwait Institute for Scientific Research at the time this paper was written. The remaining authors are with the Kuwait Institute for Scientific Research, Biotechnology Department, P.O. Box 24885, 13109, Safat, Kuwait. I.M. Banat is the corresponding author.In view of the annexation of Kuwait by Iraq in August 1990, this paper has been accepted without return to the author for attention to minor details and for approval of certain editorial changes that have been made. The Editor-in-Chief therefore assumes full responsibility for any errors or omissions. 相似文献
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Nur Athirah Yusof Noor Haza Fazlin Hashim Travis Beddoe Nor Muhammad Mahadi Rosli Md Illias Farah Diba Abu Bakar Abdul Munir Abdul Murad 《Cell stress & chaperones》2016,21(4):707-715
The ability of eukaryotes to adapt to an extreme range of temperatures is critically important for survival. Although adaptation to extreme high temperatures is well understood, reflecting the action of molecular chaperones, it is unclear whether these molecules play a role in survival at extremely low temperatures. The recent genome sequencing of the yeast Glaciozyma antarctica, isolated from Antarctic sea ice near Casey Station, provides an opportunity to investigate the role of molecular chaperones in adaptation to cold temperatures. We isolated a G. antarctica homologue of small heat shock protein 20 (HSP20), GaSGT1, and observed that the GaSGT1 mRNA expression in G. antarctica was markedly increased following culture exposure at low temperatures. Additionally, we demonstrated that GaSGT1 overexpression in Escherichia coli protected these bacteria from exposure to both high and low temperatures, which are lethal for growth. The recombinant GaSGT1 retained up to 60 % of its native luciferase activity after exposure to luciferase-denaturing temperatures. These results suggest that GaSGT1 promotes cell thermotolerance and employs molecular chaperone-like activity toward temperature assaults. 相似文献
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Differential accumulation of Xanthomonas campestris pv. campestris proteins during the interaction with the host plant: Contributions of an in vivo system 下载免费PDF全文
Cristiane Santos Mariana R. Maximiano Daiane G. Ribeiro Osmundo B. Oliveira‐Neto André M. Murad Octávio L. Franco Angela Mehta 《Proteomics》2017,17(12)
Xanthomonas campestris pv. campestris (Xcc) is the causal agent of black rot, a highly destructive disease that affects all brassicas. This work aimed to study the interaction Xcc–Brassica oleracea using an in vivo system in an attempt to identify proteins involved in pathogenicity. We used label‐free shotgun 2D‐nanoUPLC/MSE to analyze Xcc proteins in three conditions: in the interaction with susceptible (REK) and resistant (REU) plants and in culture medium (control condition). A model of Xcc–susceptible host interaction is proposed and shows that Xcc increases the abundance of several crucial proteins for infection and cell protection. In this study, we also confirmed the differential expression by qPCR analysis of selected genes. This is the first report showing a large‐scale identification of proteins in an in vivo host plant condition. Considering that most studies involving phytopathogens are in vitro (growth in culture medium or in plant extract), this work contributes with relevant information related to the plant–pathogen interaction in planta. 相似文献
77.
Nadiawati Alias Nor Muhammad Mahadi Abdul Munir Abdul Murad Farah Diba Abu Bakar Nik Azmi Nik Mahmood Rosli Md Illias 《World journal of microbiology & biotechnology》2009,25(4):561-572
A gene encoding endochitinase from Trichoderma virens UKM-1 was cloned and expressed in E. coli BL21 (DE3). Both the endochitinase gene and its cDNA sequences were obtained. The endochitinase gene encodes 430 amino acids
from an open reading frame comprising of 1,690 bp nucleotide sequence with three introns. The endochitinase was expressed
as soluble and active enzyme at 20°C when induced with 1 mM IPTG. Maximum activity was observed at 4 h of post-induction time.
SDS-PAGE showed that the purified endochitinase exhibited a single band with molecular weight of 42 kDa. Biochemical characterization
of the enzyme displayed a near neutral pH characteristic with an optimum pH at 6.0 and optimum temperature at 50°C. The enzyme
is stable between pH 3.0–7.0 and is able to retain its activity from 30 to 60°C. The presence of Mg2+ and Ca2+ ions increased the enzyme activity up to 20%. The purified enzyme has a strong affinity towards colloidal chitin and low
effect on ethyl cellulose and D-cellubiose which are non-chitin related substrates. HPLC analysis from the chitin hydrolysis
showed the release of (GlcNAc)3, (GlcNAc)2 and GlcNAc, in which (GlcNAc)2 was the main product. 相似文献
78.
Nicole M Gerardo Boran Altincicek Caroline Anselme Hagop Atamian Seth M Barribeau de Martin Vos Elizabeth J Duncan Jay D Evans Toni Gabaldón Murad Ghanim Adelaziz Heddi Isgouhi Kaloshian Amparo Latorre Andres Moya Atsushi Nakabachi Benjamin J Parker Vincente Pérez-Brocal Miguel Pignatelli Yvan Rahbé John S Ramsey Chelsea J Spragg Javier Tamames Daniel Tamarit Cecilia Tamborindeguy Caroline Vincent-Monegat Andreas Vilcinskas 《Genome biology》2010,11(2):1-17
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