Microbial indicators of climatic changes in extreme environment samples from maritime Antarctica

Abstract

The response of microrganisms to environmental and climatic changes is still unclear, because little is known about the species that inhabit sensible areas such as the Antarctic Peninsula. The biological and environmental register of the maritime Antarctica could be studied from permafrost samples, which are defined as permanently frozen sediments. The permafrost serve as a repository of various biological materials for thousands to millions of years, mainly due to its stable sub-zero temperatures, functioning as an important registry for evolutionary and biogeographic studies. The main goal of this study is to explore the diversity of Bacteria and Archaea in permafrost samples collected in the Antarctic Peninsula, which origin is from marine sediments up to 7,500 years before present, and make comparisons against the diversity of modern marine sediments of the same region. To address this goal, cultivate-independent molecular methods based on the 16S rRNA will be applied, such as denaturing gel gradient electrophoresis (DGGE), real time PCR (qPCR) and pyrosequencing. The data will be correlated to different environmental parameters to analyze which variables are responsible for the differences found in the microbial community. Such analyzes will be supported by different methods of bioinformatics and multivariate statistics. The expected results will provide the first reports on the microbial diversity in permafrosts of the Antarctic Peninsula using molecular methods, contributing for a better comprehension on how the microbial community responded to environmental and climatic changes in the past of Antarctica. (AU)