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81.
82.
The anaerobic digestion of animal fleshing from tannery solid waste was investigated with regard to hydrolytic enzymes, protease and lipase, fermentative enzyme deaminase, soluble protein and amino acids, redox potential (Eh), volatile fatty acids, ammonia and carbon dioxide up to 120 h of retention time. The release of these fermentation metabolites at various retention times greatly influenced the Eh. In the hydrolytic phase, the maximum value of Eh was ?50 mV and it reached the minimum of ?350 mV in 24 h in the fermentative phase. The minimum and maximum values of Eh were ?387 and ?452 mV at 80 h of anaerobic digestion. The release of extracellular metabolites was confirmed by HPLC and GC‐MS. In this study, we have found that the ammonia and pH had a substantial influence on the Eh during the anaerobic digestion of animal fleshing.  相似文献   
83.
Abundant and diverse fungal microbiota in the murine intestine   总被引:2,自引:0,他引:2  
Enteric microbiota play a variety of roles in intestinal health and disease. While bacteria in the intestine have been broadly characterized, little is known about the abundance or diversity of enteric fungi. This study utilized a culture-independent method termed oligonucleotide fingerprinting of rRNA genes (OFRG) to describe the compositions of fungal and bacterial rRNA genes from small and large intestines (tissue and luminal contents) of restricted-flora and specific-pathogen-free mice. OFRG analysis identified rRNA genes from all four major fungal phyla: Ascomycota, Basidiomycota, Chytridiomycota, and Zygomycota. The largest assemblages of fungal rRNA sequences were related to the genera Acremonium, Monilinia, Fusarium, Cryptococcus/Filobasidium, Scleroderma, Catenomyces, Spizellomyces, Neocallimastix, Powellomyces, Entophlyctis, Mortierella, and Smittium and the order Mucorales. The majority of bacterial rRNA gene clones were affiliated with the taxa Bacteroidetes, Firmicutes, Acinetobacter, and Lactobacillus. Sequence-selective PCR analyses also detected several of these bacterial and fungal rRNA genes in the mouse chow. Fluorescence in situ hybridization analysis with a fungal small-subunit rRNA probe revealed morphologically diverse microorganisms resident in the mucus biofilm adjacent to the cecal and proximal colonic epithelium. Hybridizing organisms comprised about 2% of the DAPI (4',6-diamidino-2-phenylindole, dihydrochloride)-positive organisms in the mucus biofilm, but their abundance in fecal material may be much lower. These data indicate that diverse fungal taxa are present in the intestinal microbial community. Their abundance suggests that they may play significant roles in enteric microbial functions.  相似文献   
84.
Abundant and Diverse Fungal Microbiota in the Murine Intestine   总被引:4,自引:0,他引:4       下载免费PDF全文
Enteric microbiota play a variety of roles in intestinal health and disease. While bacteria in the intestine have been broadly characterized, little is known about the abundance or diversity of enteric fungi. This study utilized a culture-independent method termed oligonucleotide fingerprinting of rRNA genes (OFRG) to describe the compositions of fungal and bacterial rRNA genes from small and large intestines (tissue and luminal contents) of restricted-flora and specific-pathogen-free mice. OFRG analysis identified rRNA genes from all four major fungal phyla: Ascomycota, Basidiomycota, Chytridiomycota, and Zygomycota. The largest assemblages of fungal rRNA sequences were related to the genera Acremonium, Monilinia, Fusarium, Cryptococcus/Filobasidium, Scleroderma, Catenomyces, Spizellomyces, Neocallimastix, Powellomyces, Entophlyctis, Mortierella, and Smittium and the order Mucorales. The majority of bacterial rRNA gene clones were affiliated with the taxa Bacteroidetes, Firmicutes, Acinetobacter, and Lactobacillus. Sequence-selective PCR analyses also detected several of these bacterial and fungal rRNA genes in the mouse chow. Fluorescence in situ hybridization analysis with a fungal small-subunit rRNA probe revealed morphologically diverse microorganisms resident in the mucus biofilm adjacent to the cecal and proximal colonic epithelium. Hybridizing organisms comprised about 2% of the DAPI (4′,6-diamidino-2-phenylindole, dihydrochloride)-positive organisms in the mucus biofilm, but their abundance in fecal material may be much lower. These data indicate that diverse fungal taxa are present in the intestinal microbial community. Their abundance suggests that they may play significant roles in enteric microbial functions.  相似文献   
85.
86.
Aims: The aim of the study was to optimize microbial degradation of keratinous waste and to characterize the alkaline active keratinase showing its biotechnological importance. Method and Results: An extracellular keratinase enzyme was purified from the culture medium of a bacterial isolate and the conditions were optimized. The molecular weight of DEAE‐Sepharose‐purified keratinase was determined by SDS‐PAGE. Instrumental analyses were investigated to study the mechanism of bovine hair hydrolysis. Isolate was identified as Bacillus pumilus based on phenotypic characteristics and 16S rDNA sequence. The optimized condition for its growth was pH 8 and 35°C. The molecular weight of the keratinase was estimated as 65 kDa. Activity inhibition by phenyl methyl sulphonyl fluoride confirmed keratinase as serine protease type. Instrumental analysis revealed the sulphitolysis and proteolysis involved mechanism in bovine hair hydrolysis. Conclusion: This study indicates that the isolated keratinase is an alkaline active serine protease with a high degree of activity towards bovine hair. Significance and Impact of the Study: This study examines a serine protease with high keratinolytic activity and degradation mechanism for bovine hair. The keratinolytic activity of the isolated strain and its reaction mechanism on bovine hair could show biotechnological potential in the leather industry.  相似文献   
87.
Triple trisomy in a 17-week-old fetus   总被引:1,自引:1,他引:0  
Summary Autosomal trisomies account for the majority of chromosome abnormalities associated with spontaneous miscarriages. Occasionally, double autosomal trisomies are found to be present in abortuses. This report describes the second occurrence of triple trisomy associated with fetal demise.  相似文献   
88.
Triazoles are known for their non-toxicity, higher stability and therapeutic activity. Few nucleoside (L1, L2 and L3) and non-nucleoside 1,2,3-triazoles (L4–L14) were synthesised using click chemistry and they were screened for tumor cell cytotoxicity and proliferation. Among these triazole ligands studied, nucleoside ligands exhibited higher potential than non-nucleoside ligands. The nucleoside triazole analogues, 3′-Phenyl-1,2,3- triazole-thymidine (L2) and 3′-4-Chlorophenyl-1,2,3-triazole-thymidine (L3), demonstrated higher cytotoxicity in tumor cells than in normal cells. The IC50 value for L3 was lowest (50 µM) among the ligands studied. L3 terminated cell cycle at S, G2/M phases and enhanced sub-G1 populations, manifesting induction of apoptosis in tumor cells. Confocal studies indicated that nucleoside triazole ligands (L2/L3) cause higher DNA fragmentation than other ligands. Preclinical experiments with tumor-induced mice showed greater reduction in tumor size with L3. In vitro DNA synthesis reaction with L3 exhibited higher DNA synthesis inhibition with quadruplex forming DNA (QF DNA) than non quadruplex forming DNA (NQF DNA). Tm of quadruplex DNA increased in the presence of L3, indicating its ability to enhance stability of quadruplex DNA at elevated temperature and the results indicate that it had higher affinity towards quadruplex DNA than the other forms of DNA (like dsDNA and ssDNA). From western blot experiment, it was noticed that telomerase expression levels in the tissues of tumor-induced mice were found to be reduced on L3 treatment. Microcalorimetry results emphasise that two nucleoside triazole ligands (L2/L3) interact with quadruplex DNA with significantly higher affinity (Kd≈10−7 M). Interestingly the addition of an electronegative moiety to the phenyl group of L2 enhanced its anti-proliferative activity. Though IC50 values are not significantly low with L3, the studies on series of synthetic 1,2,3-triazole ligands are useful for improving and building potential pro-apoptotic ligands.  相似文献   
89.
Focus in this Letter is made to design and synthesize a series of nineteen new 6-(4-((substituted-1H-1,2,3-triazol-4-yl)methyl)piperazin-1-yl)phenanthridine analogues employing click chemistry and evaluated for their anti-tubercular activity against Mycobacterium tuberculosis H37Rv. Among the tested compounds, 7f and 7j exhibited good activity (MIC = 3.125 μg/mL), while 8a displayed excellent activity (MIC = 1.56 μg/mL) against the growth of M. tuberculosis H37Rv. In addition, 7f, 7j and 8a compounds were subjected to cytotoxic studies against mouse macrophage (RAW264.7) cell lines and the selectivity index values are >15 indicating suitability of compounds for further drug development.  相似文献   
90.
HapR has been recognized as a quorum-sensing master regulator in Vibrio cholerae. Because it controls a plethora of disparate cellular events, the absence of a functional HapR affects the physiology of V. cholerae to a great extent. In the current study, we pursued an understanding of an observation of a natural protease-deficient non-O1, non-O139 variant V. cholerae strain V2. Intriguingly, a nonfunctional HapR (henceforth designated as HapR(V2)) harboring a substitution of glycine to aspartate at position 39 of the N-terminal hinge region has been identified. An in vitro gel shift assay clearly suggested the inability of HapR(V2) to interact with various cognate promoters. Reinstatement of glycine at position 39 restores DNA binding ability of HapR(V2) (HapR(V2G)), thereby rescuing the protease-negative phenotype of this strain. The elution profile of HapR(V2) and HapR(V2G) proteins in size-exclusion chromatography and their circular dichroism spectra did not reflect any significant differences to explain the functional discrepancies between the two proteins. To gain insight into the structure-function relationship of these two proteins, we acquired small/wide angle x-ray scattering data from samples of the native and G39D mutant. Although Guinier analysis and indirect Fourier transformation of scattering indicated only a slight difference in the shape parameters, structure reconstruction using dummy amino acids concluded that although HapR adopts a "Y" shape similar to its crystal structure, the G39D mutation in hinge drastically altered the DNA binding domains by bringing them in close proximity. This altered spatial orientation of the helix-turn-helix domains in this natural variant provides the first structural evidence on the functional role of the hinge region in quorum sensing-related DNA-binding regulatory proteins of Vibrio spp.  相似文献   
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