Expression of Candidate Cold Stress and Metabolic Related Genes in Acidithiobacillus ferrivorans PQ33 Strain Using Ferrous Iron as Electron Donor

The identification of genes involved in cold adaptations of psychrotolerant bacteria Acidithiobacillus ferrivorans is important for biomining processes that take place at low temperatures like Andean mining installations in Peru. We have performed relative quantification RT-qPCR on candidate genes to have a role in adaptations at low temperature (5°C). The candidate genes analyzed were six: Two trehalose synthesis pathway genes, trehalose synthase (treS) and malto-oligosiltrehalose trehalohydrolase (treZ) showing no overexpression at 5°C. Two diguanylate cyclases genes related to exopolymer synthesis and biofilm formation (designated as dgc-I and dgc-II in this paper) were overexpressed at 21°C. The rusA and rusB genes involved in iron oxidation showed no significant change for rusA and no expression for rusB gene in any of both conditions. Genes rpoC, gyrB and alaS were validated as reference genes. These results show congruency with trancriptomics studies about gene expression of A. ferrivorans. Furthermore, the trehalose synthesis genes show no overexpression at low temperatures suggesting that other cold adaptation mechanisms are involved.

Diversity and Bioprospecting Potential of Bacteria Isolated from the Arctic: A Preliminary Study

Bioprospecting is a search for new or better bioproducts from biological sources preferably from novel biodiversity. Molecules derived from natural products, particularly those produced by plants and microorganisms, have an excellent record of providing novel chemical structures for development as new pharmaceuticals. Bacteria living under stress are best sources for bioprospecting and also these organisms are least explored. This paper focuses on the bioprospecting and biotechnological potential of bacteria isolated from the Polar Regions. In this context, let us have a glance through the major cold adaptations of psychrophiles and their application potentials with special reference to psychrophilic enzymes. Our lab focus on identifying the biofilm inhibitors against bacterial pathogens and novel molecules of medical importance from bacteria and actinomycetes isolated from Arctic, the North Pole. We are also interested in profiling the diversity, multidrug resistance pattern and the molecular mechanisms involved in bacteria isolated from the pristine environment.