“Trade-off” in Antarctic bacteria: limnetic psychrotrophs concede multiple enzyme expressions for multiple metal resistance

Abstract

The present study examines the metal and antibiotic resistant bacteria in ice and water from lakes east and west of the Indian base camp (Maitri) in Antarctica. The isolates from western and eastern lakes showed distinct geographical differences in properties like metal resistance and enzyme expression. This may be attributed to high organic loading in the lakes on the west of Maitri. However, there was no marked geopraphical distinction in antibiotic resistance between the lakes. Bacteria from the lakes on the eastern side showed resistance to three or more metals including mercury while, those from the western were resistant to only 1-2 metals excluding mercury. Multiple enzyme expression was more pronounced in the lakes on the western side. On the eastern side multiple metal resistance was encountered in bacterial isolates associated with fewer enzyme expressions suggesting a "trade-off". Thus these Antarctic isolates from the east trade their ability to express multiple enzymes for developing resistance to multiple metals including mercury.

Microbial communities in low permeability, high pH uranium mine tailings: characterization and potential effects

“…catalase, oxidase, amylase, protease, gelatinase, urease and nitrate reductase) results were correlated with the metal ion resistance profiles of the distinct bacterial isolates, as conducted previously by De Souza et al . (). In general, bacterial isolates exhibiting multiple‐metal resistance had a considerably wider range of enzymatic activities (Fig.…”

“…Previous studies on Antarctic bacterial isolates showed an inverse correlation between multiple-metal-resistant bacteria and enzymatic potential (De Souza et al 2007).…”

“…Previous studies on Antarctic bacterial isolates showed an inverse correlation between multiple‐metal‐resistant bacteria and enzymatic potential (De Souza et al . ). Overall, their results demonstrated that the metal‐resistant strains tended to have lower enzymatic potentials.…”

“…The plates were incubated at room temperature, and growth inhibition was determined by comparison with the 5% TSA control plates. To test whether a correlation between resistance to metals and enzyme expression (De Souza et al 2007) existed, enzymatic activity assays for oxidase, catalase, amylase, nitrate reductase, gelatinase, urease and proteinase were conducted for each distinct bacterial isolate. Standard media for enzymatic testing were prepared according to the Difco BD (Sparks, MD, USA) instructions.…”

Biotechnology of siderophores in high-impact scientific fields

“…Other heavy metals present in diverse contaminated sites include arsenic, strontium and titanium (58,59). Most of these heavy metals are detrimental to living organisms but bacterial community analysis has shown that microorganisms can grow in the presence of these contaminants (21,60). Other bacterial species tend to grow in environments contaminated with petroleum-based oils or radionuclides (22,40,61).…”