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Paul R. Carlier Troy D. Anderson Dawn M. Wong Danny C. Hsu Joshua Hartsel Ming Ma Eric A. Wong Ranginee Choudhury Polo C.-H. Lam Maxim M. Totrov Jeffrey R. Bloomquist 《Chemico-biological interactions》2008,175(1-3):368
Anopheles gambiae is the major mosquito vector of malaria in sub-Saharan Africa. At present, insecticide-treated nets (ITNs) impregnated with pyrethroid insecticides are widely used in malaria-endemic regions to reduce infection; however the emergence of pyrethroid-resistant mosquitoes has significantly reduced the effectiveness of the pyrethroid ITNs. An acetylcholinesterase (AChE) inhibitor that is potent for An. gambiae but weakly potent for the human enzyme could potentially be safely deployed on a new class of ITNs. In this paper we provide a preliminary pharmacological characterization of An. gambiae AChE, discuss structural features of An. gambiae and human AChE that could lead to selective inhibition, and describe compounds with 130-fold selectivity for inhibition of An. gambiae AChE relative to human AChE. 相似文献
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Thanukrishnan Kannan Duraikkannu Loganathan Yukti Bhatia Saroj Mishra Virendra S. Bisaria 《Biocatalysis and Biotransformation》2004,22(1):1-7
The stability of almond β-glucosidase in five different organic media was evaluated. After 1 hour of incubation at 30°C, the enzyme retained 95, 91, 81, 74 and 56% relative activity in aqueous solutions [30% (v/v)] of dioxane, DMSO, DMF, acetone and acetonitrile, respectively. Transglucosylation involving p-nitrophenyl β-D-glucopyranoside as donor and β-1-N-acetamido-D-glucopyranose, which is a glycosylasparagine mimic, as acceptor was explored under different reaction conditions using almond βglucosidase and cloned Pichia etchellsii β-glucosidase II. The yield of disaccharides obtained in both reactions turned out to be 3%. Both enzymes catalyzed the formation of (1→3)- as well as (1→6)- regioisomeric disaccharides, the former being the major product in cloned β-glucosidase II reaction while the latter predominated in the almond enzyme catalyzed reaction. Use of β-1-N-acetamido-D-mannopyranose and β-1-N-acetamido-2-acetamido-2-deoxy-D-glucopyranose as acceptors in almond β-glucosidase catalyzed reactions, however, did not afford any disaccharide products revealing the high acceptor specificity of this enzyme. 相似文献
104.
Md Abu Choudhury Nicole Marsh Shahera Banu David L. Paterson Claire M. Rickard David J. McMillan 《PloS one》2016,11(1)
Skin bacteria at peripheral intravenous catheter (PIVC) insertion sites pose a serious risk of microbial migration and subsequent colonisation of PIVCs, and the development of catheter related bloodstream infections (CRBSIs). Common skin bacteria are often associated with CRBSIs, therefore the bacterial communities at PIVC skin sites are likely to have major implications for PIVC colonisation. This study aimed to determine the bacterial community structures on skin at PIVC insertion sites and to compare the diversity with associated PIVCs. A total of 10 PIVC skin site swabs and matching PIVC tips were collected by a research nurse from 10 hospitalised medical/surgical patients at catheter removal. All swabs and PIVCs underwent traditional culture and high-throughput sequencing. The bacterial communities on PIVC skin swabs and matching PIVCs were diverse and significantly associated (correlation coefficient = 0.7, p<0.001). Methylobacterium spp. was the dominant genus in all PIVC tip samples, but not so for skin swabs. Sixty-one percent of all reads from the PIVC tips and 36% of all reads from the skin swabs belonged to this genus. Staphylococcus spp., (26%), Pseudomonas spp., (10%) and Acinetobacter spp. (10%) were detected from skin swabs but not from PIVC tips. Most skin associated bacteria commonly associated with CRBSIs were observed on skin sites, but not on PIVCs. Diverse bacterial communities were observed at skin sites despite skin decolonization at PIVC insertion. The positive association of skin and PIVC tip communities provides further evidence that skin is a major source of PIVC colonisation via bacterial migration but microbes present may be different to those traditionally identified via culture methods. The results provide new insights into the colonisation of catheters and potential pathogenesis of bacteria associated with CRBSI, and may assist in developing new strategies designed to reduce the risk of CRBSI. 相似文献
105.
Y Rohilla K P Singh S R Choudhury P C Jain 《Indian journal of biochemistry & biophysics》1992,29(6):465-468
Positron annihilation studies have been carried out in two enzymes, lysozyme and catalase. Temperature dependence of the positron lifetimes in these two enzymes has been investigated. The results explained in terms of the free volume model and fluctuations between different conformational microstates of enzyme structures provide a new insight into the mechanism of bio-activity of these enzymes. 相似文献
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