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In Vitro Cellular & Developmental Biology - Plant - Rheum emodi Wall. ex Meisn is an important medicinal herb used in treating type II diabetes mellitus, arthritis, inflammation, and...  相似文献   
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Clp1 proteins are essential components of the eukaryal mRNA 3′ cleavage-polyadenylation machinery. Human Clp1 has an additional function as an RNA-specific 5′-OH polynucleotide kinase, which is implicated in RNA end healing. Yeast Clp1 has no kinase activity, although it binds ATP. Here we report that Clp1-like proteins are extant in archaea. Purification and characterization of Pyrococcus horikoshii Clp1 (PhoClp1) reveals it to be a thermostable 5′-OH polynucleotide kinase optimally active at 55°C to 85°C. PhoClp1 catalyzes transfer of the gamma phosphate from ATP (K m 16 μM) to either 5′-OH RNA or DNA ends, although it prefers RNA in a competitive situation. Increasing the monovalent salt concentration to 250 mM suppresses the DNA kinase without affecting RNA phosphorylation, suggesting that RNA is a likely substrate for this enzyme in vivo. Indeed, we show that expression of PhoClp1 in budding yeast can complement a lethal mutation in the 5′-OH RNA kinase module of tRNA ligase. PhoClp1 is a member of the P-loop phosphotransferase superfamily. Alanine mutations at the P-loop lysine (Lys49) and a conserved aspartate (Asp73) inactivate the kinase. Our studies fortify emerging evidence for an enzymatic RNA repair capacity in archaea and provide a new reagent for polynucleotide phosphorylation at high temperatures.  相似文献   
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The consumptive benefits of mangrove forests to subsistence economy receive little recognition. This paper quantifies the value of provisioning services of mangrove forests to local livelihoods in terms of forestry and fishery products. To examine the use of mangrove products, 324 households from 36 villages in the Bhitarkanika Conservation Area located in East Coast of India were surveyed using structured questionnaires. For estimating the contribution of mangrove forests to fish productivity, fish production was evaluated in three stages—inshore fishery, offshore fishery and the role of mangrove forests as nursery ground for fish and shellfish. The findings revealed that 14.2% of the fuel need of each household was being met by the forests. Other forestry products used were timber, honey and thatch grass. During the study, 14 species of fish and three of shellfish were recorded. The total catch for inshore fishery was estimated as 3.77 kg h−1 having market price of US2.25. In offshore fishery the number of species caught as well as income from the catch was higher in areas with mangroves (US 2.25. In offshore fishery the number of species caught as well as income from the catch was higher in areas with mangroves (US 44.61 h−1) than in those without mangroves (US$ 2.62 h−1). The market price of the forestry and fishery products used by the people was estimated as US$ 2.62 h−1). The market price of the forestry and fishery products used by the people was estimated as US 107 household−1 annum−1. The resources extracted from mangrove forests contributed to more than 14.5% of the total income of the household. This was around 30% for the households residing in the immediate vicinity of the forests. This study suggests that provisioning services provided by the mangrove forests are of significant importance to the coastal communities as they increase the resilience and sustainability of the local economy.  相似文献   
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Functional & Integrative Genomics - In silico derived properties on experimental validation revealed that hypothetical protein Alr2954 of Anabaena sp. PCC7120 is ADP-ribose pyrophosphatase,...  相似文献   
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