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Culture-dependent evaluation of the bacteria was carried out on gastropods, such as Monodonta lineata, Gibbula umbilicalis, Nucella lapillus and Patella intermedia, and the environmental samples (biofilm and surrounding sea water) collected from six different locations of Northern Portugal coastal area to investigate the interactions between the microbes in the viscera of gastropods and in the environment. A total of 141 isolates and 39 operational taxonomic units were identified. Phylogenetic analysis based on the 16S rRNA gene showed that bacterial isolates are highly diverse and most of them were found in other marine environment. The observed bacterial diversity was distributed over five different classes (Gammaproteobacteria, Alphaproteobacteria, Flavobacteria, Bacilli and Actinobacteria) with the greatest number of 16S rRNA gene sequence derived from the Gammaproteobacteria (77 %). Vibrio is found to be the dominant one among the different bacterial species isolated. The results suggest that the microorganisms in the environment are maintained in the viscera of the gastropods which may have a key role in the metabolic functions. 相似文献
504.
Mitochondrial heat shock protein 70 (mtHSP70) is found to play a primary role in cellular defense against physiological stress
like exposure to environmental contaminants and helpful in the maintenance of cellular homeostasis by promoting the cell survival.
In the present investigation, the environmental-stress-induced increase in mtHSP70 levels along with the quantification of
apoptosis signal regulating kinase 1 (ASK1) and thioredoxin (Trx) were measured in the liver mitochondria of grey mullets
(Mugil cephalus) collected from the polluted Ennore estuary and the unpolluted Kovalam estuary for a period of 2 years. The results showed
elevated lipid peroxide (LPO) and decreased total antioxidant capacity along with the decrease in mitochondrial viability
percentage. Mitochondrial HSP70, ASK1, and Trx levels were increased under this stress condition. A 42% increase in LPO levels
and 18% decrease in mitochondrial survivality were observed in the polluted-site fish liver mitochondria when compared to
the results of unpolluted estuary. We also report that, under observed oxidative stress condition in Ennore fish samples,
the ASK1 levels are only moderately elevated (13% increase). This may be due to mitochondrial-HSP70-induced adaptive tolerance
signaling for the activation of Trx (22% increase) which suppresses the ASK1 expression thereby promoting the cell survival
that leads to the maintenance of the cellular homeostasis. 相似文献
505.
D. Ashok S. Ravi B. Vijaya Lakshmi A. Ganesh Shaik Adam 《Russian Journal of Bioorganic Chemistry》2016,42(3):323-331
A novel series of 1,2,3-triazolo-carbazole chalcones were synthesized by the Claisen-Schmidt condensation reaction followed by the copper catalyzed Huisgen (2 + 3) cycloaddition reaction by conventional as well as microwave irradiation methods. The structures of the newly synthesized compounds were established on the basis of IR, 1H NMR, 13C NMR, and mass spectral data. All the compounds were screened in vitro for antibacterial and antifungal activities. 相似文献
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Usha Natraj K. S. N. Iyer Vijaya Raghavan Smita Mahale Jacintha Pereira 《Journal of biosciences》1990,15(4):341-350
The antigenecity of tryptic fragments of reduced and carboxymethylated chicken riboflavin carrier protein were studied. The
tryptic sites of the native riboflavin carrier protein bound to riboflavin were inaccessible. The molecular weight and the
elution profile on high performance liquid chromatography (TSK 545 DEAE) were unaltered at an enzyme to substrate ratio of
1:31. However, carboxymethylated riboflavin carrier protein could be cleaved into 3 or 4 fragments at an enzyme to substrate
ratio of 1:250 or 1:125. Chromatographic separation of the tryptic fragments on high pressure liquid chromatography (TSK 545
DEAE) revealed the presence of two fragments with different elution profiles but similar molecular weight 26 ±2 kDa. Only
one fragment (associated with peak 2) had the ability to displace chicken riboflavin carrier protein in an homologous chicken
riboflavin carrier protein radioimmunoassay. Thus, carboxymethylated ribotlavin carrier protein which does not compete with
chicken riboflavin carrier protein in the radioimmunoassay, on mild trypsinization generates a fragment which interacts with
chicken riboflavin carrier protein in radioimmunoassay. 相似文献
509.
M Vijaya N Sukanya H S Savithri N A Rao 《Indian journal of biochemistry & biophysics》1991,28(4):252-256
A naturally occurring inhibitor of serine hydroxymethyltransferase (EC 2.1.2.1) in mung bean seedlings extracts was purified by ammonium sulphate precipitation, phenyl-Sepharose chromatography followed by heating to release the inhibitor bound to the protein. The inhibitor had an absorption maximum at 200 nm, was not precipitated by trichloroacetic acid, was dialysable and resistant to inactivation by heating at 98 degrees C for 4 hr, protease and ribonuclease digestion; but was acid labile. The chromatographically pure preparation inhibited both mung bean and sheep liver SHMT. Qualitative and quantitative analyses indicated that it contained a carbohydrate moiety, an O-amino and vicinal diol groups. Paper electrophoresis at pH 4.3 suggested that the inhibitor was positively charged. 相似文献