Bacterial diversity and distribution in the holocene sediments of a northern temperate lake

David M. Nelson, Samuel Ohene-Adjei, Feng Sheng Hu, Isaac K.O. Cann, Roderick I. Mackie

Research output: Contribution to journalArticlepeer-review

Abstract

Sediments contain an abundance of microorganisms. However, the diversity and distribution of microorganisms associated with sediments are poorly understood, particularly in lacustrine environments. We used banding patterns from denaturing gradient gel electrophoresis (DGGE) and 16S rDNA sequences to assess the structure of bacterial communities in the Holocene sediments of a meromictic lake in Minnesota. Cluster analysis of the DGGE banding patterns indicates that the early- and middle-Holocene samples group separately from the late-Holocene samples. About 79% of the recovered bacterial sequences cluster with the α-, β-, δ-, ε-, and γ- Proteobacteriaceae and Firmicutes. The remaining ∼21% lack cultured representatives. The taxonomic lineages of bacteria differ statistically among the early-, middle-, and late-Holocene samples, although the difference is smallest between early- and middle-Holocene samples. Early- and middle-Holocene samples are dominated by ε-Proteobacteriaceae, and late-Holocene samples are dominated by sequences from uncultured subphyla. We only recovered δ-Proteobacteriaceae in late-Holocene sediments and α- and γ- Proteobacteriaceae in late- and middle-Holocene sediments. Diversity estimates derived from early-, middle-, and late-Holocene clone libraries indicate that the youngest (late-Holocene) samples had significantly greater bacterial diversity than the oldest (early-Holocene) samples, and the middle-Holocene samples contained intermediate levels of diversity. The observed patterns of diversity may be caused by increased bacterial niche-partitioning in younger sediments that contain a greater abundance of labile organic matter than older sediments.

Original languageEnglish (US)
Pages (from-to)252-263
Number of pages12
JournalMicrobial Ecology
Volume54
Issue number2
DOIs
StatePublished - Aug 2007

ASJC Scopus subject areas

  • Ecology, Evolution, Behavior and Systematics
  • Ecology
  • Soil Science

Fingerprint Dive into the research topics of 'Bacterial diversity and distribution in the holocene sediments of a northern temperate lake'. Together they form a unique fingerprint.

Cite this