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101.
Bioprocess and Biosystems Engineering - The genes for dextransucrase and dextranase were cloned from the genomic regions of Leuconostoc mesenteroides MTCC 10508 and Streptococcus mutans MTCC 497,...  相似文献   
102.
Bioprocess and Biosystems Engineering - In the present study, the effect of irradiance on growth performance of Scenedesmus obliquus was investigated, and various non-linear growth models were...  相似文献   
103.
The polyadenylic acid [poly(A)] tail of mRNA plays a noteworthy role in the initiation of the translation, maturation, and stability of mRNA. It also significantly contributes to the production of alternate proteins in eukaryotic cells. Hence, it has recently been recognized as a prospective drug target. Binding affinity of bis(N-p-tolylbenzohydroxamato)Cobalt(II), [N-p-TBHA-Co(II)] (1) and bis(N-p-naphthylbenzohydroxamato)Copper(II), [N-p-NBHA-Cu(II)] (2) complexes with poly(A) have been investigated by biophysical techniques namely, absorption spectroscopy, fluorescence spectroscopy, diffuse reflectance infrared Fourier transform spectroscopy, circular dichroism spectroscopy, viscometric measurements and through molecular docking studies. The intrinsic binding constants (Kb) of complexes were determined following the order of N-p-TBHA-Co(II)] > N-p-NBHA-Cu(II), along with hyperchromism and a bathochromic shift for both complexes. The fluorescence quenching method revealed an interaction between poly(A)-N-p-TBHA-Co(II)/poly(A)-N-p-NBHA-Cu(II). The mode of binding was also determined via the fluorescence ferrocyanide quenching method. The increase in the viscosity of poly(A) that occurred from increasing the concentration of the N-p-TBHA-Co(II)/N-p-NBHA-Cu(II) complex was scrutinized. The characteristics of the interaction site of poly(A) with N-p-TBHA-Co(II)/N-p-NBHA-Cu(II) were adenine and phosphate groups, as revealed by DRS-FTIR spectroscopy. Based on these observations, a partial intercalative mode of the binding of poly(A) has been proposed for both complexes. Circular dichroism confirmed the interaction of both the complexes with poly(A). The molecular docking results illustrated that complexes strongly interact with poly(A) via the relative binding energies of the docked structure as ?259.39eV and ?226.30eV for N-p-TBHA-Co(II) and N-p-NBHA-Cu(II) respectively. Moreover, the binding affinity of N-p-TBHA-Co(II) is higher in all aspects than N-p-NBHA-Cu(II) for poly(A).  相似文献   
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105.
Probiotics and Antimicrobial Proteins - Bovicin is a type AII lantibiotic, possessing two β-methyllanthionine and a disulfide bridge encoded by bovA gene hitherto unknown a couple of decades...  相似文献   
106.
Probiotics and Antimicrobial Proteins - The present study was to investigate the utilization of prebiotics by Lactobacillus rhamnosus NCDC 298 and its synergistic adversary effect on both...  相似文献   
107.
Batch cultures of Chlorella vulgaris and C. variegata reproducing about twice every 5 d within 0-15 d had vegetative cells and autospore mother cells in the ratio of about 19 : 1. Continuous slow or negligible and/or no growth in > 15-d-old control cultures or in young cultures supplied with the antibiotics streptomycin, penicillin, amoxycillin (10-1000 ppm) or tetracycline (10, 100 ppm), and pesticides carbofuran, gammaxine, moticop or iralon (1-100 ppm) was due to slow autospore mother cells dehiscence (leading to an increase in their percentage); while negligible and/or no growth of both algal species in sewage water (100, 25%), detergent (0.1-1%), petrol or kerosene (5-20 %), benzene, toluene or phenol (5, 10%) and pesticides rogor or endosulfan (1, 10 ppm) was due to vegetative cells failure to differentiate into auto-spore mother cells (leading to decreased/zero autospore mother cells percentage) and/or rapid death of all cells. C. variegata was equally or slightly more sensitive to different chemical stress than C. vulgaris.  相似文献   
108.
A rational approach has been applied to design a new environmentally acceptable and industrially viable enzymatic scouring process. Owing to the substrate specificity, the selection of enzymes depends on the structure and composition of the substrate, i.e. cotton fibre. The structure and composition of the outer layers of cotton fibre has been established on the basis of thorough literature study, which identifies wax and pectin removal to be the key steps for successful scouring process. Three main issues are discussed here, i.e. benchmarking of the existing alkaline scouring process, an evaluation of several selected acidic and alkaline pectinases for scouring, and the effect of wax removal treatment on pectinase performance. It has been found that the pectinolytic capability of alkaline pectinases on cotton pectin is nearly 75% higher than that of acidic pectinases. It is concluded that an efficient wax removal prior to pectinase treatment indeed results in improved performance in terms of hydrophilicity and pectin removal. To evaluate the hydrophilicity, the structural contact angle (theta) was measured using an auto-porosimeter.  相似文献   
109.
Visceral leishmaniasis (VL) caused by Leishmania donovani is a major parasitic disease prevalent in endemic regions of Bihar in India. In the absence of good chemotherapeutic options, there is a need to develop an effective vaccine against VL which should be dependent on the generation of a T helper type 1 (Th1) immune response. We have shown that soluble proteins from promastigote of a new clinical isolate of L. donovani (2001) ranging from 68 to 97.4 kDa (F2 fraction), induce Th1 responses in the peripheral blood mononuclear cells of cured Leishmania patients and hamsters and also showed significant prophylactic potential. To understand the nature of F2 proteins, it was further characterized using 2-DE, MALDI-TOF and MALDI-TOF/TOF-MS. In all, 63 spots were cut from a CBB stained gel for analysis and data was retrieved for 52 spots. A total of 33 proteins were identified including six hypothetical/unknown proteins. Major immunostimulatory proteins were identified as elongation factor-2, p45, heat shock protein (HSP)70, HSP83, aldolase, enolase, triosephosphate isomerase, protein disulfideisomerase and calreticulin. This study substantiates the usefulness of proteomics in characterizing a complex protein fraction (F2) map of soluble L. donovani promastigote antigen identified as Th1 stimulatory for its potential as vaccine targets against VL.  相似文献   
110.
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