The genotypic diversity and lipase production of some thermophilic bacilli from different genera

Abstract Thermophilic 32 isolates and 20 reference bacilli were subjected to Rep-PCR and ITS-PCR fingerprinting for determination of their genotypic diversity, before screening lipase activities. By these methods, all the isolates and references could easily be differentiated up to subspecies level from each other. In screening assay, 11 isolates and 7 references were found to be lipase producing. Their extracellular lipase activities were measured quantitatively by incubating in both tributyrin and olive oil broths at 60 °C and pH 7.0. During the 24, 48 and 72-h period of incubation, the changes in the lipase activities, culture absorbance, wet weight of biomass and pH were all measured. The activity was determined by using pNPB in 50 mM phosphate buffer at pH 7.0 at 60 °C. The lipase production of the isolates in olive oil broths varied between 0.008 and 0.052, whereas these values were found to be 0.002-0.019 (U/mL) in the case of tyributyrin. For comparison, an index was established by dividing the lipase activities to cell biomass (U/mg). The maximum thermostable lipase production was achieved by the isolates F84a, F84b, and G. thermodenitrificans DSM 465T (0.009, 0.008 and 0.008 U/mg) within olive oil broth, whereas G. stearothermophilus A113 displayed the highest lipase activity than its type strain in tyributyrin. Therefore, as some of these isolates displayed higher activities in comparison to references, new lipase producing bacilli were determined by presenting their genotypic diversity with DNA fingerprinting techniques.

Induced defence responses of contrasting bread wheat genotypes under differential salt stress imposition.

Plants, being sessile in nature, have developed mechanisms to cope with high salt concentrations in the soil. In this study, the effects of NaCl (50-200 mM) on expression of high-affinity potassium transporters (HKTs), antioxidant enzymes and their isozyme profiles were investigated in two contrasting bread wheat (Triticum aestivum L.) genotypes viz., HD2329 (salt-sensitive) and Kharchia65 (salt-tolerant). Kharchia65 can successfully grow in salt affected soils, while HD2329 cannot tolerate salt stress. Differential expression studies of two HKT genes (TaHKT2;1.1 and TaHKT2;3.1) revealed their up-regulated expression (~1.5-fold) in the salt-sensitive HD2329 and down-regulated (~5-fold) inducible expression in the salt-tolerant genotype (Kharchia65). Specific activity of antioxidant enzymes, viz. superoxide dismutase (SOD), peroxidase (POX), ascorbate peroxidase (APX), catalase (CAT) and glutathione reductase (GR) was found to be higher in the salt-tolerant genotype. Isozyme profile of two (POX and GR) antioxidant enzymes showed polymorphism between salt-tolerant and salt-sensitive genotypes. A new gene TaHKT2;3.1 was also identified and its expression profile and role in salt stress tolerance in wheat was also studied. Partial sequences of the TaHKT2;1.1 and TaHKT2;3.1 genes from bread wheat were submitted to the EMBL GenBank database. Our findings indicated that defence responses to salt stress were induced differentially in contrasting bread wheat genotypes which provide evidences for functional correlation between salt stress tolerance and differential biochemical and molecular expression patterns in bread wheat.

Genotyping of High Risk Human Papillomavirus (HPV) Among Cervical Precancer and Cancer Patients.

Introduction: Human papillomavirus (HPV) is a DNA virus which has tropism for epithelial cells, is the major etiological factor for development of cervical precancerous and cancerous lesions. Nearly 100 diff erent types of HPV have been characterized and thereare a large number of other types. HPV infection is one of the most common causes of sexually transmitted disease in both men and women worldwide. It is associated with a variety of clinical conditions that range from innocuous lesions to cancer. Genital HPV types are divided into high and low-risk types, according to the oncogenic potential. Molecular and epidemiologic studies have solidifi ed the association between high risk HPV types (especially HPV-16 and HPV-18) and cervical squamous cell carcinoma. HPV infection is often transient and self-limiting but infection may persists and progress to high grade lesions and cancer. In addition to persistent high-risk HPV infection, other viral factors such as high viral loads, HPV variants, infections with multiple high-risk HPV types and genetic predisposition contribute to the development of cervical cancer. Th e aim of the present study was to detect HPV DNA and identify high risk HPV genotype among women having cervical intraepithelial neoplasia and carcinoma and to evaluate potential effi cacy of prophylactic HPV vaccine. Methods: Cervical swab from histopathologically diagnosed CIN (n=51) and carcinoma (n=39) patients were taken and high risk HPV DNA was detected by HC II assay. Polymerase Chain Reaction was used to identify high risk HPV genotype. Result: HPV DNA was detected in 41 (45.56%) patients by HC II assay. HPV type 16 was detected in 27 (81.82%) followed by type 18 in 3 (9.09%) and type 45 in 2 (6.06%) cases of cervical carcinoma. Among precancerous cases, only type 16 was detected. Conclusion: Knowledge based on HPV prevalence and genotype could be used to predict the effi cacy of cost eff ective prophylactic vaccine, introduction of newer generation vaccine and management of cervical carcinoma.

Insertion-deletions burden in copy number polymorphisms of the Tibetan population.

BACKGROUND: Many studies have been conducted to identify either insertions-deletions (inDels) or copy number variations (CNVs) in humans, but few studies have been conducted to identify both of these forms coexisting in the same region. AIMS AND OBJECTIVES: To map the functionally significant sites within human genes that are likely to influence human traits and diseases. MATERIALS AND METHODS: In this report, we describe an inDel map in the 1051 Tibetan CNV regions obtained through CNV genotyping using Affymetrix Genome-wide single nucleotide polymorphism 6.0 chip. InDel polymorphisms in these copy number polymorphism regions were identified with a computational approach using the 2500 deoxyribonucleic acid sequences obtained from the 1000 Genome Project. RESULTS: The study identified a total of 95935 inDels that range from 1 bp to several bps in length which were found scattered across regulatory regions, exons and in introns of genes underlying the CNVs. A study on the distribution of inDels revealed that the majority of inDels were found in coding regions of the genome than the noncoding, while within the genes, inDels in intron regions were more followed by exonic regions and finally the regulatory regions. CONCLUSION: Study of inDels in CNV regions contribute to the enhanced understanding of the role played by the two variations and their collective influence on the genome. Further, a collection of these inDel genetic markers will aid in genetic mapping, further understanding of the phenotypic variability, identification of disease genes and in detecting novel CNVs.