A postdoc and a PhD position are available within the Austrian Science Fund (FWF) project The cold microbial majority: Ecophysiology, biogeography, and genomics of psychrophilic sulfate-reducing microorganisms in arctic marine sediments
Project description. Molecular biology techniques have provided insights into the tremendous genetic diversity, abundance, and distribution of microorganisms on planet Earth. However, we still have a very limited understanding of the metabolic function and thus ecological role of most environmental microorganisms because only a minute fraction of this microbial majority is cultivated. Prime examples are sulfate-reducing microorganisms (SRM), ubiquitous inhabitants of anoxic seafloor sediments and key catalysts of the marine sulfur and carbon cycles. Although more than 90% of the seafloor area is exposed to temperatures permanently below 4°C, most cultivated SRM are meso- or thermophiles and thus the physiological and genomic features of cold-adapted SRM are poorly characterized. This project aims to fill this gap by using a unique, cultivation-independent approach that combines innovative high-throughput microarray methods and high-resolution single cell techniques to investigate psychrophilic SRM in arctic sediments of the Svalbard archipelago. Based on a 16S rRNA (gene) phylogeography survey of bacteria and archaea, a microarray will be developed for the Svalbard sediment microbiota and applied for identification of psychrophilic SRM that metabolize isotope-labeled substrates supplied at in situ concentrations. The isotope array analyses will reveal (i) the substrate utilization profiles of SRM detected at one sampling site and (ii) the distribution pattern of actively acetate-oxidizing SRM among different Svalbard fjords. These analyses will be complemented by using single cell resolution techniques to quantify the newly identified SRM (by fluorescence in situ hybridization) and to confirm their ecophysiology (by microautoradiography, Raman-microspectroscopy, and/or secondary ion mass spectrometry imaging; NanoSIMS). Finally, by employing targeted single cell genomics approaches where sorting of individual SRM cells is based on their physiology or phylogeny, the genomes of different arctic SRM will be sequenced and analyzed for features that sustain the observed metabolic capabilities under cold temperatures. In summary, this integrated combination of cutting-edge methods has great potential to (i) systematically yield unprecedented insights into the biogeography, ecophysiology, and genetic makeup of a microbial guild that is of global importance in the oceans and (ii) provide a conceptual foundation for the investigation of other uncultivated members of the microbial majority.
Required qualifications. We are looking for highly motivated and independently working scientists with interest in collaborative & applied microbial ecology research. Applicants should have a strong conceptual and practical background on the application of molecular and isotope-labelling techniques for characterizing the identity and ecophysiology of microbial community members. Experience in one or more of the following areas/techniques will be of advantage: microbial ecology of sulfate-reducing microorganisms, rRNA amplicon pyrosequencing, DNA microarrays/PhyloChips, genomics, bioinformatics, isotope probing of uncultivated microbes, and cultivation of anaerobic microorganisms. Proficiency in spoken and written English is mandatory.
Conditions of appointment. We offer up to 3 years of appointment as a postdoctoral scientist or PhD student according to the salary scheme of the Austrian Science Fund (FWF). The University of Vienna is an equal opportunity employer.
Mode of application. To apply, please send an email (subject: Postdoc Arctic SRM or PhD Arctic SRM) to Dr. Alexander Loy, firstname.lastname@example.org containing a pdf-file with your application, a detailed CV (including a brief description of research interests, previous employments, and publication list), reprints of your two most important published articles, and contact details of at least two references (letters of recommendation are optional).
Job start date is February 2013.