| Autor: |
Vander Schaaf NA; Division of Natural Sciences, Indiana Wesleyan University, 4201 South Washington St., Marion, IN 46953-4974, USA. Nicole.VanderSchaaf@vai.org., Cunningham AM; Division of Natural Sciences, Indiana Wesleyan University, 4201 South Washington St., Marion, IN 46953-4974, USA. annamgcunningham@hotmail.com., Cluff BP; Department of Biology, MidAmerica Nazarene University, 2030 E. College Way, Olathe, KS 66062, USA. brandonpcluff@gmail.com., Kraemer CK; Department of Biology, MidAmerica Nazarene University, 2030 E. College Way, Olathe, KS 66062, USA. ckraemer@email.arizona.edu., Reeves CL; Division of Natural Sciences, Indiana Wesleyan University, 4201 South Washington St., Marion, IN 46953-4974, USA. chelsealreeves@gmail.com., Riester CJ; Division of Natural Sciences, Indiana Wesleyan University, 4201 South Washington St., Marion, IN 46953-4974, USA. carlijriester@trevecca.edu., Slater LK; Division of Natural Sciences, Indiana Wesleyan University, 4201 South Washington St., Marion, IN 46953-4974, USA. laurenkayslater@gmail.com., Madigan MT; Department of Microbiology, Southern Illinois University, 1125 Lincoln Dr., Carbondale, IL 62901, USA. madigan@micro.siu.edu., Sattley WM; Division of Natural Sciences, Indiana Wesleyan University, 4201 South Washington St., Marion, IN 46953-4974, USA. matthew.sattley@indwes.edu. |
| Abstrakt: |
The permanently ice-covered lakes of the McMurdo Dry Valleys, Antarctica are distinctive ecosystems that consist strictly of microbial communities. In this study, water samples were collected from Lake Vanda, a stratified Dry Valley lake whose upper waters (from just below the ice cover to nearly 60 m) are highly oligotrophic, and used to establish enrichment cultures. Six strains of psychrotolerant, heterotrophic bacteria were isolated from lake water samples from a depth of 50 or 55 m. Phylogenetic analyses showed the Lake Vanda strains to be species of Nocardiaceae, Caulobacteraceae, Sphingomonadaceae, and Bradyrhizobiaceae. All Lake Vanda strains grew at temperatures near or below 0 °C, but optimal growth occurred from 18 to 24 °C. Some strains showed significant halotolerance, but no strains required NaCl for growth. The isolates described herein include cold-active species not previously reported from Dry Valley lakes, and their physiological and phylogenetic characterization broadens our understanding of these limnologically unique lakes. |
