Abundance, Distribution, and Diversity of Viruses in Alkaline, Hypersaline Mono Lake, California

• Published in: Microbial ecology Vol. 47; no. 1; pp. 9 - 17
• Main Authors: Jiang, S., Steward, G., Jellison, R., Chu, W., Choi, S.
• Format: Journal Article
• Language: English
• Published: New York, NY Springer-Verlag New York Inc 01.01.2004; Springer; Springer Nature B.V
• Subjects: Ammonia - analysis; Anoxic waters; Aquatic environment; Bacteriology; Bacteriophages; Bacteriophages - isolation & purification; Base Sequence; Biological and medical sciences; Bottom water; California; Chemical stratification; Chemocline; Cluster Analysis; Community composition; DNA Probes; Electric Conductivity; Electrophoresis; Electrophoresis, Gel, Pulsed-Field; Fresh Water - microbiology; Fresh Water - virology; Freshwater; Fundamental and applied biological sciences. Psychology; Gels; Genome, Viral; Lakes; Limnology; Meromixis; Microbiology; Microscopy, Fluorescence; Miscellaneous; Molecular Sequence Data; Oxygen; Oxygen - analysis; Oxygen depletion; Phytoplankton; Proteobacteria - genetics; Proteobacteria - virology; Regression Analysis; Sequence Analysis, DNA; Sodium Chloride - analysis; Sulfides - analysis; Surface water; Temperature; Virology; Viruses; Water analysis; Water samples; Water sampling; California; United States; North America; America; USA, California, Mono L; USA, California; Oxygen; Anoxia; Microbiology; Respiratory disease; Environmental factor; Genotype; Ecology; Infection; Virus; Aquatic environment; Pulsed field electrophoresis; Bacteriosis; Bacteria; Isolate; Genome; Phage
• ISSN: 0095-3628; 1432-184X
• DOI: 10.1007/s00248-003-1023-x

Mono Lake is a large (180 km²), alkaline (pH ∼ 10), moderately hypersaline (70-85 g kg⁻¹) lake lying at the western edge of the Great Basin. An episode of persistent chemical stratification (meromixis) was initiated in 1995 and has resulted in depletion of oxygen and accumulation of ammonia and sulfide beneath the chemocline. Although previous studies have documented high bacterial abundances and marked seasonal changes in phytoplankton abundance and community composition, there have been no previous reports on the occurrence of viruses in this unique lake. Based on the high concentrations and diversity of microbial life in this lake, we hypothesized that planktonic viruses are also abundant and diverse. To examine the abundance and distribution of viruses and bacteria, water samples were collected from four stations along 5 to 15 vertical depths at each station. Viral abundance ranged from 1 × 10⁸ to 1 × 10⁹ mL⁻¹, among the highest observed in any natural aquatic system examined so far. Increases (p < 0.1) in viral densities were observed in the anoxic bottom water at multiple stations. However, regression analysis indicated that viral abundance could not be predicted by any single environmental parameter. Pulsed field gel electrophoresis revealed a diverse viral community in Mono Lake with genome sizes ranging from ∼ 14 to >400 kb with most of the DNA in the 30 to 60 kb size range. Cluster analysis grouped the anoxic bottom-water viral community into a unique cluster differentiating it from surface and mid-water viral communities. A hybridization study using an indigenous viral isolate as a probe revealed an episodic pattern of temporal phage distribution with strong niche stratification between oxic and anoxic waters.