Psychrophilic Bacteria and Enzyme Activity in Antarctic Ice Environments

Abstract

Psychrophilic organisms exhibit many adaptation mechanisms that enable them to survive at low temperatures ranging from −20 to 20 °C. Among other characteristics, these organisms produce cold-active enzymes with considerable biotechnological potential. The purpose of this study was to isolate and characterize bacteria from ice core samples collected on Horseshoe, Hovgaard, and Nansen Islands. Microorganisms from the latter two locations have been investigated only to a limited extent to date. Based on the phylogenetic analysis of 16S rRNA nucleotide sequences, eight bacterial isolates, including Sporosarcina, Arthrobacter, Bacillus, Luteimonas, Rhodococcus, and Methylobacterium were ultimately isolated and identified. Additionally, Raman and Fourier Transform Infrared Spectroscopy were used to analyze the biochemical properties of the bacteria. The bacterial culture’s enzyme activity was assessed utilizing semiquantitative and screening techniques, and the API ZYM analysis revealed high enzyme activity, particularly for naphthol-AS-BI-phosphohydrolase, leucine aminopeptidase, esterase, lipase, and esterase. This study clarifies the biochemical characteristics of Antarctic bacteria and offers new perspectives on their enzymatic activity at various temperatures and resistance to antibiotics.