Biology subjects

Bhattacharyya, M. K.

Publications and source records attributed to Bhattacharyya, M. K..

4 recordsLinked to original sources

bioRxiv2023

A soybean pattern recognition receptor conferring broad-spectrum pathogen and pest resistance regulates expression of several NLR receptor proteins

Overexpressors of Glycine max disease resistant 1 (GmDR1) exhibits broad-spectrum resistance against Fusarium virguliforme, soybean cyst nematode (SCN), spider mites, and soybean aphids in soybean. To understand the mechanisms of broad-spectrum immunity mediated by GmDR1, we investigated the transcriptomes of a strong and a weak GmDR1-overexpressors following treatment with chitin, a pathogen- and pest-associated molecular pattern (PAMP) found in these organisms. The strong and weak GmDR1-overexpressors exhibited altered expression of 6,098 and 992 genes, respectively, as compared to the nontransgenic control following chitin treatment. However, only 192 of these genes exhibited over two-fold changes in expression levels in both strong and weak GmDR1-overexpressors as compared to the control. MapMan analysis of the 192 genes revealed 64 biotic stress-related genes, of which 53 were induced and 11 repressed as compared to the control. The 53 chitin-induced genes include nine that encode receptor kinases, 13 encode nucleotide-binding leucine-rich repeat (NLR) receptor proteins, seven encoding WRKY transcription factors, four ethylene response factors, and three MYB-like transcription factors. Investigation of a subset of these genes revealed three receptor protein kinases, seven NLR proteins, and one WRKY transcription factor genes that are induced following F. virguliforme and SCN infection. The integral plasma membrane GmDR1 protein most likely recognizes PAMPs including chitin and activates transcription of genes encoding receptor kinases and NLR proteins. GmDR1 could be a pattern recognition receptor that regulates the expression of several NLRs for expression of PAMP-triggered immunity and/or priming the effector triggered immunity.

plant biology↗

bioRxiv2022

Thiovibrio frasassiensis gen. nov., sp. nov., an autotrophic, elemental sulfur disproportionating bacterium isolated from sulfidic karst sediment, and proposal of Thiovibrionaceae fam. nov.

A novel, autotrophic, mesophilic bacterium, strain RS19-109T, was isolated from sulfidic stream sediments in the Frasassi Caves, Italy. The cells of this strain grew chemolithoautotrophically under anaerobic conditions while disproportionating elemental sulfur (S0) and thiosulfate, but not sulfite with bicarbonate/CO2 as a carbon source. Autotrophic growth was also observed with molecular hydrogen as an electron donor, and S0, sulfate, thiosulfate, nitrate, and ferric iron as electron acceptors. Oxygen was not used as an electron acceptor and sulfide was not used as an electron donor. Weak growth was observed with sulfate as an electron acceptor and organic carbon as electron donors and carbon sources. The strain also showed weak growth by fermentation of tryptone. Strain RS19-109T was found to be phylogenetically distinct based on 16S rRNA gene sequence similarity (89.2%) to its closest relative, Desulfurivibrio alkaliphilus AHT2T. The draft genome sequence for strain RS19-109T had average nucleotide identity, average amino acid identity, and in silico DNA-DNA hybridization values of 72.2%, 63.0%, and 18.3%, respectively, compared with the genome sequence of D. alkaliphilus AHT2T. On the basis of its physiological and genomic properties, strain RS19-109T is proposed as the type strain of a novel species of a novel genus, Thiovibrio frasassiensis gen. nov., sp. nov. A novel family, Thiovibrionaceae fam. nov., is proposed to accommodate Thiovibrio within the order Desulfobulbales.

microbiology↗

bioRxiv2022

Cold Tolerance is Governed by Diverse Genetic Mechanisms Including Those Regulated by NB-LRR-type Receptor Proteins in Arabidopsis.

Cold stress adversely affects the growth and development of plants and limits the geographical distribution of crop plants. Accumulation of spontaneous mutations shapes the adaptation of plant species to diverse climatic conditions. Genome-wide association study of the phenotypic variation gathered by a newly designed phenomic platform with that of the single nucleotide polymorphic (SNP) loci across the genomes of 417 Arabidopsis natural variants collected from various geographical regions revealed 33 candidate genes for cold tolerance. Investigation of at least two independent mutants for 29 of these genes identified 16 cold tolerance genes controlling diverse genetic mechanisms. This study identified five genes encoding novel leucine-rich repeat domain-containing proteins, including three nucleotide-binding site leucine-rich repeat (NBS-LRR) proteins. Among the 16 identified cold tolerance genes, ADS2 and ACD6 are the only two cold tolerance genes identified earlier. The comparatively little overlap between the genes identified in this genome-wide association study of natural variants with those discovered previously through forward and reverse genetic approaches suggests that cold tolerance is a complex physiological process governed by a large number of genetic mechanisms. Short SummaryCold stress adversely affects the growth and development of plants and limits the geographical distribution of crop plants. Genome-wide association study of the phenotypic variation of Arabidopsis natural variants with that of the single nucleotide polymorphic loci followed by T-DNA insertion mutant analyses of 29 candidate genes led to assigning cold tolerance function for the first time to 14 genes including three nucleotide-binding sites leucine repeat region (NB-LRR) protein genes. The comparatively little overlap between the genes identified in this study with those discovered previously suggests that cold tolerance is governed by a complex network of multiple genetic mechanisms.

plant biology↗

bioRxiv2021

A Chimeric Peptide Inhibits Red Blood Cell Invasion by Plasmodium falciparum with Hundredfold Increased Efficacy

Inhibition of tight junction formation between two malaria parasite proteins, apical membrane antigen 1 and rhoptry neck protein 2, crucial for red blood cell invasion, prevents the disease progression. In this work, we have utilized a unique approach to design a chimeric peptide, prepared by fusion of the best features of two peptide inhibitors, that has displayed parasite growth inhibition, in-vitro, with nanomolar IC50, which is hundredfold better than any of its parent peptides. Further, to gain structural insights, we computationally modeled the hybrid peptide on its receptor.

biochemistry↗