Molecular docking and simulation studies against nucleoside diphosphate kinase (NDK) of Pseudomonas aeruginosa with secondary metabolite identified by genome mining from paenibacillusehimensis.

Pseudomonas aeruginosa is one of the leading opportunistic pathogens that causes nosocomial pneumonia and mostly in people with cystic fibrosis. In the present study, an in-silicoapproach was adopted to identify the novel drug target against Pseudomonas aeruginosa by employing subtractive genomics and molecular docking studies. Each step in the subtractive genomics scrutinized the bacterial proteome and determined a potential drug target against Pseudomonas aeruginosa. 71 essential proteins were obtained from the subcellular localization method that resides in the extracellular region. Metabolic pathways were studied to elucidate the unique pathways where the involvement of proteins present in the pathogen was predicted and a total of 6 unique pathways were determined. By, Genome mining of the source organism Paenibacillusehimensis, 9 ligands were obtained. The molecular docking analysis between the binding site of target protein NDK and ligands was carried out by employing the AutoDock Vina tool. Based on the highest binding affinity, Paenibactin, AnabaenopeptinNZ857 and Nostamide A complex with NDK protein with a lower binding energy of -7.5 kcal/mol, -7.4and -7.2 kcal/molrespectively were considered for the simulation studies. Molecular dynamics simulation studies showed the ligand in complex with protein was highly stable and rigid for a duration of 150 ns. For Paenibactin, AnabaenopeptinNZ857 and Nostamide Acomplex with protein, RMSD plot showed a deviation of ∼0.2-0.3 nm till ∼30ns/50 ns-110ns and further stabilized. The radius of the gyration plot clearly showed that the values stayed at ∼1.45 nm- 1.55 nm showing compactness and stability. The SASA stayed at the range ∼80nm2 and at least one total number of hydrogen bonds was shown throughout the 150 ns simulation for all three possible ligand-protein complexes. In the RMSF plot, the maximum fluctuation was ranged from ∼0.4-0.42 nm at the range between ∼57ns-60ns.The Paenibactin, AnabaenopeptinNZ857 and Nostamide A complex with NDK protein showed a stable, rigid and compact interaction throughout the simulation of duration 150 ns.Communicated by Ramaswamy H. Sarma.

p53 polymorphism and association of human papillomavirus in oral submucous fibrosis and oral squamous cell carcinoma: A case-control study.

INTRODUCTION: The tumor-suppressor p53 protein is inactivated by the human papillomavirus (HPV) E6 oncoprotein, causing polymorphism of the p53 at codon 72 of exon either proline (Pro) or arginine (Arg). Specific allele predisposition has been reported in the literature. The association between the p53 allele and HPV types has been reported. We analyzed the association between p53 polymorphism at codon 72 and HPV 16 and 18 genotypes in control, oral submucous fibrosis (OSF) and oral squamous cell carcinoma (OSCC). MATERIALS AND METHODS: Of the total 90 cases, biopsy tissues of all groups (30 cases of OSF, OSCC and control each) were collected to extract DNA. Polymerase chain reaction was used to detect HPV 16 and 18 and alleles of codon 72 in p53 were evaluated in all the samples. RESULTS: In control, OSF and OSCC samples showed the presence HPV 63.3%, 33.3% and 60%, respectively. In OSF, HPV 16 and 18 was detected in four and four cases, respectively, whereas in OSCC, HPV 16 and 18 was detected in ten and nine cases, respectively. In all three groups, predominantly, Arg/Arg protein was present followed by Pro/Pro and Arg/Pro. Among the control, Arg/Arg type protein was frequently seen followed by Arg/Pro, Pro/Pro in the presence of HPV. OSF and OSCC were associated homologous genes in the presence of HPV. CONCLUSION: The definite association between p53 codon 72, polymorphism and HPV 16 and 18 was seen in OSCC with low frequency in OSF. Frequency of homozygous genotype is at high risk in the presence of HPV 16 and 18 in developing OSCC.

Genomic DNA of MCF-7 breast cancer cells not an ideal choice as positive control for PCR amplification based detection of Mouse Mammary Tumor Virus-Like Sequences.

The identification of the etiology of breast cancer is a crucial research issue for the development of an effective preventive and treatment strategies. Researchers are exploring the possible involvement of Mouse Mammary Tumor Virus (MMTV) in causing human breast cancer. Hence, it becomes very important to use a consistent positive control agent in PCR amplification based detection of MMTV-Like Sequence (MMTV-LS) in human breast cancer for accurate and reproducible results. This study was done to investigate the feasibility of using genomic DNA of MCF-7 breast cancer cells to detect MMTV-LS using PCR amplification based detection. MMTV env and SAG gene located at the 3' long terminal repeat (LTR) sequences were targeted for the PCR based detection. No amplification was observed in case of the genomic DNA of MCF-7 breast cancer cells. However, the 2.7 kb DNA fragment comprising MMTV env and SAG LTR sequences yielded the products of desired size. From these results it can be concluded that Genomic DNA of MCF-7 cell is not a suitable choice as positive control for PCR or RT-PCR based detection of MMTV-LS. It is also suggested that plasmids containing the cloned genes or sequences of MMTV be used as positive control for detection of MMTV-LS.

Teratoma of palatine tonsil in a neonate.

Among many causes of respiratory distress and feeding difficulties in the neonatal period, a tumor involving oropharyngeal region is very rare. But still rarer is the unique presentation of this case of teratoma tonsil with intermittent attacks of choking with cyanosis.