Group Overview

Agriculture and industries are two pillars of socio-economic progress of a society or country. While agriculture is mostly a reflection of crop yield, a large number of industries are driven by microbes or microbial products. According to one of the estimates, the human population is increasing rapidly, and is likely to increase from 7.3 billion to 9.6 billion by 2050. Hence, the agricultural produce must increase substantially to meet the growing demand. It has also been estimated that the production of rice, which accounts for nearly 23% of human consumption of carbohydrates, itself should increase to at least 800 million metric tons from the current production of 585 million metric tons. With the increase in human population it is also expected that industrial activities, including that based on microbes and microbial products would increase, which in turn might require microbes of improved quality and efficiency. Keeping these in view, the efforts in this group will aim at finding ways and means for increasing agriculture productivity in environmentally challenged ecosystems and address the current demand and the future needs of industry for improved microbe-based technologies.

Group Members:

Major activities undertaken during last 5 years

Microbial biotechnology group is working on the genome-based reconstruction of metabolic model and functional analysis of pathways linked to phenotypic expression in bacteria, especially in extremophiles, which represent a largely untapped resource with unlimited potential for novel beneficial products. Reconstruction of metabolic model and functional analysis of pathways involved in bio-geochemical cycle, synthesis of metabolites & drug resistance in bacteria have significant benefits not only in terms of environmental issues but also in terms of pharmaceuticals.

Crop improvement group works on biochemical and molecular aspects of salt tolerance in plants using halophyte as a model. The group interest lies in identification and characterization of key regulatory and functional genes involved in salt tolerance from naturally salt-tolerant halophytes and their subsequent mobilization to crop species for generating transgenic plants. This research program has the potential of transforming large areas of cultivated land in India (<5 Million Ha) affected by salinity and thereby enhancing agricultural productivity in coastal areas.

Plant biotechnology group works primarily on the biochemical and molecular basis of grain filling process in rice. This is considering the fact that poor grain filling in the basal spikelets of rice panicle results in yield loss as high as 50 %. Hence, the effort is being made to identify the key factor(s) determining the grain filling process by a comparative study of the expression pattern of the genes in the spikelets located on an apical and basal region of the panicle for biotechnology intervention, which may increase the yield of rice by 30-50 %. The group is interested in gene mining from halophytes, the extremophiles of plant origin, for key genes imparting salt and/or drought tolerance in them and identifying the genes/proteins involved in tolerance of a crop plant to a pathogen for developing transgenic crop plants with the desired trait for the benefit of agriculture.

Plant molecular biology group works on the development of efficient promoters for enhanced expression of the transgenes in transgenic plants because transcriptional promoters (wild type) of plant/non-plant origin are usually long and weak. The strength and tissue specificity of native promoters are being enhanced by manipulating the ‘cis-architecture’ through ‘cis-engineering’ thereby generating improved synthetic promoters. Over the last three decades, synthetic promoters have gained extensive popularity in plant biotechnology for regulating plant gene expression. This group is also interested in plant molecular farming in which important genes from the human origin are expressed in the plant for bulk production.

Key achievements of the group

•     Large-scale sequencing of more than 6,000 ESTs have been carried out from the libraries constructed from three halophytes and classification of these ESTs have been undertaken.
•     96 potential genes have been identified based on the gene regulation and expression studies and detailed analysis has suggested that genes involved in antioxidant pathways are most ideal for genetic manipulation.
• PM-H+ATPase has been found to be a crucial enzyme in maintenance of ion-homeostasis and salt tolerance in plants.

• We have found that accumulation of glycine betaine in the halophyte Suaeda maritima is regulated at the level of PEAMT (phosphoethanolamine N-methyltransferase).

• We have identified that salt tolerance in plants is mediated through miRNAs targeting auxin response factor (ARF) and serine/threonine kinase.

• We demonstrate that compact panicle architecture is detrimental for growth as well as sucrose synthase activity of developing rice kernels.
•     We observed that high expression of ethylene receptors and ethylene signaling components has an antagonistic effect on grain filling in rice. Grain filling in rice is significantly improved by the application of ethylene action blocker.
•     Demonstrated Arabidopsis TGA3 and WRKY53 physically interact to regulate stress induced gene expression.
•     Characterized 112 mature microRNAs specific to Tomato leaf curl New Delhi virus (ToLCNDV) infection in tomato plants and submitted more than 53 novel microRNAs specific to ToLCNDV infection in tomato plants to ‘mirbase’ database.
• Developed 27 useful plant expression vectors coupled to recombinant promoters for boosting sustainable agricultural biotechnology under stress conditions.

• Developed two efficient bi-directional promoters one with tripartite enhancer and other with tissue specificity and stress adaptability.

• Developed methods for utilization of plant-derived recombinant human β-defensins (hBD-1 and hBD-2) for averting salmonellosis.

• Invented a versatile gene expression binary vector pSiM24 useful for transient as well as stable expression of foreign genes in plants with high efficiency.
• Based on the polyphasic approach we have reported 15 new microbes from our Institute. These microbes are being used for the elucidation of novel metabolic pathways and biomolecules.
• Shortest thiosulfate dependent electron transport chain in Thiomonas bhubaneswarensis strain S10 (DSM 18181T) has been elucidated.

• The role of proline residue for arsenate reductase activity in Pannonibacter indicus strain HT23T (DSM 23407T) has been characterized.

• A recombinant construct has been developed as a whole cell biosensor for the detection of arsenic in drinking water for which a patent has been filed.
• Taxonomic and functional characteristics of microbial communities and their correlation with physicochemical properties of four geothermal springs in Odisha, India has been elucidated.
• Novel SXT/R391 integrating conjugative elements in the genome of a halophilic bacterium Marinomonas fungi has been characterized.

• Halostable, solvent tolerant novel β-endoglucanase has been overexpressed and characterized.