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991.
Fu Lijun An Xinli Li Dong Zhou Lijian Tian Yun Zheng Tianling 《World journal of microbiology & biotechnology》2011,27(12):2949-2956
The bacterium BS02 which is closely related to the genus Vibrio sp. and capable of inhibiting the toxic dinoflagellate Alexandrium tamarense was isolated from a mangrove area in Zhangjiangkou, Fujian Province, China. The bacterium was not species-specific since
it displayed varying degrees of lysing activities against eight of the eighteen algae tested. There was a close interaction
between initial bacterial and A. tamarense cell densities, indicating that algal growth was prompted at low bacterial concentrations, while the number of the alga cells
was reduced at high concentrations. Alga-lysing characterization of Vibrio sp. BS02 suggested that the alga-lysing substance was extracellularly produced, less than 500 in molecular weight, as well
as non proteinaceous, stable under wide range of temperature and pH conditions, UV radiation, repeated freezing and thawing
and heavy metal treatments. These findings suggested that BS02 could play an important role in controlling harmful algal blooms. 相似文献
992.
993.
The two-stage culture system consisting of green vegetative growth and reddish inductive production stages has been widely accepted for the production of astaxanthin using Haematococcuspluvialis. However, little has been known about the appropriate cellular phase of H.pluvialis for transferring into the astaxanthin inductive conditions. In this study, we determined the optimal growth phase of H.pluvialis for transferring into the second production stage. Astaxanthin productivities were correlated with growth phases, as senescent green phases could increase more than 10-fold greater than juvenile green phases. Our results clearly demonstrated the appropriateness of the senescent vegetable cells for transferring into the production stage, due to the increased capacity to accumulate astaxanthin. 相似文献
994.
Biodiesel synthesis and conformation of Burkholderia cepacia lipase (BCL) were studied in 19 different room temperature ionic liquids (RTLLs) with a range of cation and anion structures. Overall, anion selection had a greater influence on biodiesel conversion than cation choice. RTILs containing Tf2N- and PF6- anions were suitable reaction media, while RTIL of [OmPy][BF4] was the best reaction medium with a biodiesel yield of 82.2±1.2%. RTILs with strong water miscible properties showed very low biodiesel yields. Conformational analysis by FT-IR revealed that higher biodiesel conversion in RTILs was correlated with a low tendency in α-helix content of BCL. An ultrasound-assisted biocatalysis process in RTILs was used to improve mass transfer rate, leading to 83% reduction of the reaction time for biodiesel production. 相似文献
995.
Yun Chau LongAlexei Kharitonenkov 《生物化学与生物物理学报:疾病的分子基础》2011,1812(7):791-795
The family of fibroblast growth factors (FGFs) consisting now of 22 members is generally considered to control a wide range of biological functions such as development, differentiation and survival. However, research during the past decade provided substantial evidence that a so called “hormone-like” subgroup of FGFs, comprised of FGF19, FGF21 and FGF23, is involved in the regulation of diverse metabolic pathways to control glucose, lipid, bile acid, phosphate and vitamin D metabolism. The unique properties of these FGFs include predominant production of the factors in selective tissues, their abundance in the blood due to the lack of extracellular heparin-mediated sequestration, and highly specific tissue-targeted action via engagement of their respective co-receptors. The important metabolic context of FGF19, FGF21, and FGF23 actions has revealed important novel roles for FGFs and provided significant means to explore an opportunity for therapeutic targeting of these factors and their corresponding pathways. 相似文献
996.
Cho BO Jin CH Park YD Ryu HW Byun MW Seo KI Jeong IY 《Bioscience, biotechnology, and biochemistry》2011,75(7):1306-1311
Isoegomaketone (IK) is an essential oil component of Perilla frutescens (L.), but the mechanism by which IK induces apoptosis has never been studied. The purpose of this study was to elucidate the IK-induced apoptotic pathway in DLD1 human colon cancer cells. We observed that IK treatment over 24 h significantly inhibited cell viability in a dose-dependent manner. We also found that IK triggered cleavage of PARP. Moreover, IK treatment resulted in cleavage of caspase-8, -9, and -3 in a dose- and time-dependent manner. IK treatment also resulted in cleavage of Bid and translocation of Bax, and triggered the release of cytochrome c from the mitochondria to the cytoplasm. Furthermore, it resulted in the translocation of apoptosis inducing factor (AIF), a caspase-independent mitochondrial apoptosis factor, from the mitochondria into the nucleus. Overall, these results suggest that IK induces apoptosis through caspase-dependent and capase-independent pathways in DLD1 cells. 相似文献
997.
Superoxide (O2•−) is implicated in inflammatory states including arteriosclerosis and ischemia-reperfusion injury. Cobalamin (Cbl) supplementation is beneficial for treating many inflammatory diseases and also provides protection in oxidative-stress-associated pathologies. Reduced Cbl reacts with O2•− at rates approaching that of superoxide dismutase (SOD), suggesting a plausible mechanism for its anti-inflammatory properties. Elevated homocysteine (Hcy) is an independent risk factor for cardiovascular disease and endothelial dysfunction. Hcy increases O2•− levels in human aortic endothelial cells (HAEC). Here, we explore the protective effects of Cbl in HAEC exposed to various O2•− sources, including increased Hcy levels. Hcy increased O2•− levels (1.6-fold) in HAEC, concomitant with a 20% reduction in cell viability and a 1.5-fold increase in apoptotic death. Pretreatment of HAEC with physiologically relevant concentrations of cyanocobalamin (CNCbl) (10-50 nM) prevented Hcy-induced increases in O2•− and cell death. CNCbl inhibited both Hcy and rotenone-induced mitochondrial O2•− production. Similarly, HAEC challenged with paraquat showed a 1.5-fold increase in O2•− levels and a 30% decrease in cell viability, both of which were prevented with CNCbl pretreatment. CNCbl also attenuated elevated O2•− levels after exposure of cells to a Cu/Zn-SOD inhibitor. Our data suggest that Cbl acts as an efficient intracellular O2•− scavenger. 相似文献
998.
999.
Yun EY Hwang JS Yoon YI Ahn MY Kim NJ Kwon OY Lee WJ Goo TW 《Archives of insect biochemistry and physiology》2011,77(3):145-162
To examine the expression profile of oxidative stress responsive genes in Spodoptera litura, we constructed a cDNA library from S. litura injected with hydrogen peroxide (H(2)O(2)). Using a microarray chip composed of 2,964 cDNAs, we screened gene expression at 1, 3, 5, 7, and 9 h post H(2)O(2) injection. Data were clustered into 15 groups of genes that behave similarly across each time course. Seventy-three genes were identified as being at least twofold up- or downregulated after treatment with H(2)O(2) in S. litura. We constructed expressed sequence tags (ESTs) for genes that changed at least twofold after treatment with H(2)O(2) . The functional classification of these ESTs based on Gene Ontology showed that the ESTs are rich in genes involved in oxidoreductase activity (5.7%), defense (14.3%), cellular process (22.9%), and development (17.1%). 相似文献
1000.