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91.
Novel thermophilic and thermostable lipolytic enzymes from a Thailand hot spring metagenomic library 总被引:2,自引:0,他引:2
Tirawongsaroj P Sriprang R Harnpicharnchai P Thongaram T Champreda V Tanapongpipat S Pootanakit K Eurwilaichitr L 《Journal of biotechnology》2008,133(1):42-49
Functional screening for lipolytic enzymes from a metagenomic library (origin: Jae Sawn hot spring, Thailand) resulted in isolation of a novel patatin-like phospholipase (PLP) and an esterase (Est1). PLP contained four conserved domains similar to other patatin-like proteins with lipid acyl hydrolase activity. Likewise, sequence alignment analysis revealed that Est1 can be classified as a family V bacterial lipolytic enzyme. Both PLP and Est1 were expressed heterologously as soluble proteins in E. coli and exhibited more than 50% of their maximal activities at alkaline pH, of 7-9 and 8-10, respectively. In addition, both enzymes retained more than 50% of maximal activity in the temperature range of 50-75 degrees C, with optimal activity at 70 degrees C and were stable at 70 degrees C for at least 120 min. Both PLP and Est1 exhibited high V(max) toward p-nitrophenyl butyrate. The enzymes had activity toward both short-chain (C(4) and C(5)) and long chain (C(14) and C(16)) fatty acid esters. The isolated enzymes, are therefore, different from other known patatin-like phospholipases and esterases, which usually show no activity for substrates longer than C(10). We suggest that PLP and EstA enzymes are novel and have a; b potential use in industrial applications. 相似文献
92.
Persistence of DNA threads in human anaphase cells suggests late completion of sister chromatid decatenation 总被引:1,自引:0,他引:1
PICH (Plk1-interacting checkpoint helicase) was recently identified as an essential component of the spindle assembly checkpoint
and shown to localize to kinetochores, inner centromeres, and thin threads connecting separating chromosomes even during anaphase.
In this paper, we have used immuno-fiber fluorescence in situ hybridization and chromatin-immunoprecipitation to demonstrate
that PICH associates with centromeric chromatin during anaphase. Furthermore, by careful analysis of PICH-positive anaphase
threads through FISH as well as bromo-deoxyurdine and CREST labeling, we strengthen the evidence that these threads comprise
mainly alphoid centromere deoxyribonucleic acid. Finally, by timing the addition of ICRF-193 (a specific inhibitor of topoisomerase-II
alpha) to cells synchronized in anaphase, we demonstrate that topoisomerase activity is required specifically to resolve PICH-positive
threads during anaphase (as opposed to being required to prevent the formation of such threads during earlier cell cycle stages).
These data indicate that PICH associates with centromeres during anaphase and that most PICH-positive threads evolve from
inner centromeres as these stretch in response to tension. Moreover, they show that topoisomerase activity is required during
anaphase for the resolution of PICH-positive threads, implying that the complete separation of sister chromatids occurs later
than previously assumed.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Wang and Schwarzbraun both contributed equally to this study. 相似文献
93.
Charames GS Ramyar L Mitri A Berk T Cheng H Jung J Bocangel P Chodirker B Greenberg C Spriggs E Bapat B 《Human genetics》2008,124(5):535-541
94.
Kreutter KD Lu T Lee L Giardino EC Patel S Huang H Xu G Fitzgerald M Haertlein BJ Mohan V Crysler C Eisennagel S Dasgupta M McMillan M Spurlino JC Huebert ND Maryanoff BE Tomczuk BE Damiano BP Player MR 《Bioorganic & medicinal chemistry letters》2008,18(9):2865-2870
2-Cyano-6-fluorophenylacetamide was explored as a novel P2 scaffold in the design of thrombin inhibitors. Optimization around this structural motif culminated in 14, which is a potent thrombin inhibitor (Ki = 1.2 nM) that exhibits robust efficacy in canine anticoagulation and thrombosis models upon oral administration. 相似文献
95.
Xu G Searle LL Hughes TV Beck AK Connolly PJ Abad MC Neeper MP Struble GT Springer BA Emanuel SL Gruninger RH Pandey N Adams M Moreno-Mazza S Fuentes-Pesquera AR Middleton SA Greenberger LM 《Bioorganic & medicinal chemistry letters》2008,18(12):3495-3499
We herein disclose a novel series of 4-aminopyrimidine-5-carbaldehyde oximes that are potent and selective inhibitors of both EGFR and ErbB-2 tyrosine kinases, with IC(50) values in the nanomolar range. Structure-activity relationship (SAR) studies elucidated a critical role for the 4-amino and C-6 arylamino moieties. The X-ray co-crystal structure of EGFR with 37 was determined and validated our design rationale. 相似文献
96.
Hepatitis C virus (HCV) infects an estimated 170 million people worldwide, the majority of whom develop a chronic infection which can lead to severe liver disease, and for which no generally effective treatment yet exists. A promising target for treatment is the internal ribosome entry site (IRES) of HCV, a highly conserved domain within a highly variable RNA. Never before have the ribosome binding sites of any IRES domains, cellular or viral, been directly characterized. Here, we reveal that the HCV IRES sequences most closely associated with 80S ribosomes during protein synthesis initiation are a series of discontinuous domains together comprising by far the largest ribosome binding site yet discovered. 相似文献
97.
Lily Anjilvel 《CMAJ》1973,108(1):60-62
Eleven cases of ischemic heart disease with or without myocardial infarction from two families in the Baie Verte Peninsula, Newfoundland, were studied. All were found to have hyperlipoproteinemia of the familial types. The family trees were traced and a definite genetic pattern detected. Diets were found to be rich in saturated fats, salt and carbohydrates. It is suggested that detection of similar families may play a significant role in the field of preventive medicine. 相似文献
98.
Katherina Walz Devon Cohen Paul M. Neilsen Joseph Foster II. Francesco Brancati Korcan Demir Richard Fisher Michelle Moffat Nienke E. Verbeek Kathrine Bjørgo Adriana Lo Castro Paolo Curatolo Giuseppe Novelli Clemer Abad Cao Lei Lily Zhang Oscar Diaz-Horta Juan I. Young David F. Callen Mustafa Tekin 《Human genetics》2015,134(2):181-190
99.
Lambert K Sørensen Birthe M Rasmussen Joe O Boison Lily Keng 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1997,694(2):25
A high-performance liquid chromatographic method based on C18 solid-phase extraction and ultraviolet detection at 323 nm of analytes derivatized with benzoic anhydride and 1,2,4-triazole mercuric chloride solution was developed for the simultaneous determination of amoxicillin, penicillin G (benzylpenicillin), ampicillin, oxacillin, cloxacillin and dicloxacillin residues in raw milk. The detection limit of the method was 1.3 μg/l for penicillin G; 1.4 μg/l for amoxicillin, oxacillin and cloxacillin, 1.5 μg/l for ampicillin and 2.7 μg/l for dicloxacillin. The mean recovery was 95–102% for amoxicillin, penicillin G and ampicillin, 92–98% for oxacillin and cloxacillin and 87–94% for dicloxacillin, measured by using an internal standard. The relative repeatability standard deviation was 4–9% on level 4–15 μg/l, respectively, 2–7% on level 30–40 μg/l. 相似文献
100.
Resolving the northern hemisphere source region for the long‐distance dispersal event that gave rise to the South American endemic dung moss Tetraplodon fuegianus 下载免费PDF全文