Systematic and Applied Microbiology 28 (2005) 541–554 Molecular detection and isolation from Antarctica of methylotrophic bacteria able to grow with methylated sulfur compounds S. Azra Moosvi a , Ian R. McDonald b,1 , David A. Pearce c , Donovan P. Kelly d , Ann P. Wood a,Ã a Department of Life Sciences, King’s College London, Franklin Wilkins Building, 150 Stamford Street, London SE1 9NH, UK b Department of Biological Sciences, University of Warwick, Coventry CV4 7AL, UK c British Antarctic Survey, Natural Environment Research Council, High Cross, Madingley Road, Cambridge CB3 0ET, UK d Department of Biological Sciences, University of Warwick, Coventry CV4 7AL, UK Abstract This study is the first demonstration that a diverse facultatively methylotrophic microbiota exists in some Antarctic locations. PCR amplification of genes diagnostic for methylotrophs was carried out with bacterial DNA isolated from 14 soil and sediment samples from ten locations on Signy Island, South Orkney Islands, Antarctica. Genes encoding the mxaF of methanol dehydrogenase, the fdxA for Afipia ferredoxin, the msmA of methanesulfonate monooxygenase, and the 16S rRNA gene of Methylobacterium were detected in all samples tested. The mxaF gene sequences corresponded to those of Hyphomicrobium, Methylobacterium, and Methylomonas. Over 30 pure cultures of methylotrophs were isolated on methanesulfonate, dimethylsulfone, or dimethylsulfide from ten Signy Island lakes. Some were identified from 16S rRNA gene sequences (and morphology) as Hyphomicrobium species, strains of Afipia felis, and a methylotrophic Flavobacterium strain. Antarctic environments thus contain diverse methylotrophic bacteria, growing on various C 1 -substrates, including C 1 -sulfur compounds. r 2005 Elsevier GmbH. All rights reserved. Keywords: Antarctica; Signy island; Hyphomicrobium; Afipia; Methylobacterium; Methylotrophy; Methanesulfonate; Methanol dehydrogenase Introduction Numerous studies of the indigenous bacterial micro- flora of Antarctica have revealed a considerable phylogenetic diversity of bacteria from a variety of habitats [16,18,22–24,38,68,69,74,75,78,82,83], but little is known about the occurrence of methylotrophs, other than methanotrophs, in Antarctica. Methane oxidation by bacteria has been shown in several habitats [8] and isolates from Antarctic meromictic lakes proved to be of a novel obligate methanotroph, Methylosphaera hanso- nii, growing only with methane or methanol [17]. We described novel methylotrophic strains of Afipia felis from the Antarctic [64], but there has been no assessment of the diversity of facultatively methylo- trophic genera that might use methylated compounds present in Antarctica. Methylotrophic Afipia was reported from only three locations, and we needed to determine if this genus was indeed ubiquitous. Free- living Afipia strains have been reported from numerous ARTICLE IN PRESS www.elsevier.de/syapm 0723-2020/$ - see front matter r 2005 Elsevier GmbH. All rights reserved. doi:10.1016/j.syapm.2005.03.002 Ã Corresponding author. Tel.: +44 20 7848 4344; fax: +44 20 7848 4500. E-mail address: ann.p.wood@kcl.ac.uk (A.P. Wood). 1 Present address: Department of Biological Sciences, University of Waikato, Private Bag 3105, Hamilton, New Zealand.