Nichols_etal_2005.pdf (118.94 kB)
Effects of Incubation Temperature on Growth and Production of Exopolysaccharides by an Antarctic Sea Ice Bacterium Grown in Batch Culture
journal contribution
posted on 2023-05-25, 23:14 authored by Nichols, CAM, John BowmanJohn Bowman, Guezennec, JThe sea ice microbial community plays a key role in the productivity of the Southern Ocean. Exopolysaccharide (EPS) is a major component of the exopolymer secreted by many marine bacteria to enhance survival and is abundant in sea ice brine channels, but little is known about its function there. This study investigated the effects of temperature on EPS production in batch culture by CAM025, a marine bacterium isolated from sea ice sampled from the Southern Ocean. Previous studies have shown that CAM025 is a member of the genus Pseudoalteromonas and therefore belongs to a group found to be abundant in sea ice by culture-dependent and -independent techniques. Batch cultures were grown at 2°C, 10°C, and 20°C, and cell number, optical density, pH, glucose concentration, and viscosity were monitored. The yield of EPS at 2°C and 10°C was 30 times higher than at 20°C, which is the optimum growth temperature for many psychrotolerant strains. EPS may have a cryoprotective role in brine channels of sea ice, where extremes of high salinity and low temperature impose pressures on microbial growth and survival. The EPS produced at 2°C and 10°C had a higher uronic acid content than that produced at 20°C. The availability of iron as a trace metal is of critical importance in the Southern Ocean, where it is known to limit primary production. EPS from strain CAM025 is polyanionic and may bind dissolved cations such at trace metals, and therefore the presence of bacterial EPS in the Antarctic marine environment may have important ecological implications.
History
Publication title
Applied and Environmental MicrobiologyVolume
71Article number
7Number
7Pagination
3519-3523ISSN
0099-2240Publication status
- Published
Rights statement
RQF Nominated mmc 09/10 Checked with Lynn decided on open access 10/10 http://www.journals.asm.org/subscriptions/freefulltext.shtml If a funding agency does not itself maintain such a site, then ASM allows the author to fulfill that requirement by depositing the manuscript in an appropriate institutional or subject-based open repository established by a government or noncommercial entity. ASM copyright transfer agreements have been altered to permit this.Repository Status
- Open
Usage metrics
Categories
No categories selectedKeywords
Licence
Exports
RefWorks
BibTeX
Ref. manager
Endnote
DataCite
NLM
DC