Extremophiles (2017) 21:891–901
Characterization of a cold‑active bacterium isolated from the
South Pole “Ice Tunnel”
Michael T. Madigan
· Megan L. Kempher
· Kelly S. Bender
· Paul Sullivan
W. Matthew Sattley
· Alice C. Dohnalkova
· Samantha B. Joye
Received: 9 May 2017 / Accepted: 23 June 2017 / Published online: 5 July 2017
© Springer Japan KK 2017
that yielded strain UC-1 revealed over 1200 operational
taxonomic units (OTUs) distributed across eight major
classes of Bacteria. Many of the OTUs were Clostridia and
Bacteriodia and some of these were probably of wastewa-
ter origin. However, a signiﬁcant fraction of the OTUs were
Proteobacteria and Actinobacteria of likely environmental
origin. Our results shed light on the lower temperature lim-
its to life and the possible existence of functional microbial
communities in ultra-cold environments.
Keywords Antarctic microbiology · Amundsen–Scott
South Pole Station · Pseudomonas psychrophila
During the past 40 years, the extensive microbial diversity
of Antarctica has been revealed gradually from a combina-
tion of culture-dependent and culture-independent studies.
Microbial ecologists have probed Antarctic terrestrial, gla-
cial, subglacial, and aquatic environments for their micro-
bial inhabitants, and in particular, environments in and
around the McMurdo Dry Valleys (Bottos et al. 2014; Cary
et al. 2010; Clocksin et al. 2007; Cowan 2014; Jung et al.
2004; Karr et al. 2005, 2006; Kwon et al. 2017; Mikucki
et al. 2009, 2015; Miteva 2008; Miteva et al. 2004; Sattley
and Madigan 2006, 2007, 2010; Smith et al. 2006; Takacs
and Priscu 1998; Tang et al. 2013; Tregoning et al. 2015).
A variety of microbial habitats exist in ice (Abyzov 1995;
Boetius et al. 2015; Price 1999; Priscu et al. 1998), and
a number of Bacteria and Archaea have been described
from icy as well as terrestrial Dry Valley habitats (Takacs-
Vesbach et al. 2010). In addition, samples of accretion
ice from interior Antarctic subglacial lakes harbor micro-
bial communities (Christner et al. 2001, 2008; Karl et al.
Abstract Extremely cold microbial habitats on Earth
(those below −30 °C) are rare and have not been surveyed
for microbes as extensively as environments in the 0 to
−20 °C range. Using cryoprotected growth media incu-
bated at −5 °C, we enriched a cold-active Pseudomonas
species from −50 °C ice collected from a utility tunnel
for wastewater pipes under Amundsen–Scott South Pole
Station, Antarctica. The isolate, strain UC-1, is related to
other cold-active Pseudomonas species, most notably P.
psychrophila, and grew at −5 °C to +34–37 °C; growth
of UC-1 at +3 °C was signiﬁcantly faster than at +34 °C.
Strain UC-1 synthesized a surface exopolymer and high
levels of unsaturated fatty acids under cold growth condi-
tions. A 16S rRNA gene diversity screen of the ice sample
This paper is dedicated to the memory of our good friend and
colleague, Dr. Vladimir A. Samarkin, a major contributor to
Antarctic Dry Valley research in the SBJ laboratory.
Communicated by A. Oren.
* Michael T. Madigan
Department of Microbiology, Southern Illinois University,
Carbondale, IL 62901, USA
Present Address: Department of Microbiology and Plant
Biology, University of Oklahoma, Norman, OK 73019, USA
United States Antarctic Program, Amundsen-Scott Station,
Division of Natural Sciences, Indiana Wesleyan University,
Marion, IN 46953, USA
Paciﬁc Northwest National Laboratory, Richland, WA 99352,
Department of Marine Sciences, University of Georgia,
Athens, GA 30602, USA