Draft Genome Sequence of Highly Virulent Race 4/Biovar 3 of Ralstonia solanacearum CaRs_Mep Causing Bacterial Wilt in Zingiberaceae Plants in India.

The genome of Ralstonia solanacearum CaRs_Mep, a race 4/biovar 3/phylotype I bacterium causing wilt in small cardamom and other Zingiberaceae plants, was sequenced. Analysis of the 5.7-Mb genome sequence will aid in better understanding of the genetic determinants of host range, host jump, survival, pathogenicity, and virulence of race 4 of R. solanacearum.

Genetic analysis of plant endophytic Pseudomonas putida BP25 and chemo-profiling of its antimicrobial volatile organic compounds.

Black pepper associated bacterium BP25 was isolated from root endosphere of apparently healthy cultivar Panniyur-5 that protected black pepper against Phytophthora capsici and Radopholus similis - the major production constraints. The bacterium was characterized and mechanisms of its antagonistic action against major pathogens are elucidated. The polyphasic phenotypic analysis revealed its identity as Pseudomonas putida. Multi locus sequence typing revealed that the bacterium shared gene sequences with several other isolates representing diverse habitats. Tissue localization assays exploiting green fluorescence protein expression clearly indicated that PpBP25 endophytically colonized not only its host plant - black pepper, but also other distantly related plants such as ginger and arabidopsis. PpBP25 colonies could be enumerated from internal tissues of plants four weeks post inoculation indicated its stable establishment and persistence in the plant system. The bacterium inhibited broad range of pathogens such as Phytophthora capsici, Pythium myriotylum, Giberella moniliformis, Rhizoctonia solani, Athelia rolfsii, Colletotrichum gloeosporioides and plant parasitic nematode, Radopholus similis by its volatile substances. GC/MS based chemical profiling revealed presence of Heneicosane; Tetratetracontane; Pyrrolo [1,2-a] pyrazine-1,4-dione, hexahydro-3-(2-methylpropyl); Tetracosyl heptafluorobutyrate; 1-3-Eicosene, (E)-; 1-Heneicosanol; Octadecyl trifluoroacetate and 1-Pentadecene in PpBP25 metabolite. Dynamic head space GC/MS analysis of airborne volatiles indicated the presence of aromatic compounds such as 1-Undecene;Disulfide dimethyl; Pyrazine, methyl-Pyrazine, 2,5-dimethyl-; Isoamyl alcohol; Pyrazine, methyl-; Dimethyl trisulfide, etc. The work paved way for profiling of broad spectrum antimicrobial VOCs in endophytic PpBP25 for crop protection.

DPP-IV inhibitory potential of naringin: an in silico, in vitro and in vivo study.

The incretin based therapies are an emerging class of antidiabetic drugs, with two categories: one is glucagone like peptide-1 (GLP-1) agonists and the other one is dipeptidyl peptidase (CD26; DPP-IV) inhibitors. However, in the DPP-IV inhibitors category only few compounds are commercially available and also have some undesirable effects. Therefore, in the present work we tried to explore a naturally occurring compound naringin for its potential DPP-IV inhibition and antidiabetic potential. It is noteworthy that this compound is abundantly present in orange peel and thus may provide cost effective treatment for diabetes, especially type 2 diabetes mellitus. In the present study, we have conducted virtual docking study and observed tight binding of naringin, as shown by higher negative values of H bond lengths, while in vitro DPP-IV inhibition assay has also shown better inhibition by naringin. In vivo study, in response to 10 days administration of 40 mg/kg of naringin twice daily to Wistar albino rats, inhibited the serum levels of DPP-IV activity, random glucose concentration with concomitant increase in insulin levels. All the comparisons were made with the standard commercially available drug sitagliptin.