Isolation and characterization of aggregate-forming sulfate-reducing and purple sulfur bacteria from the chemocline of meromictic Lake Cadagno, Switzerland

Document Type

Article

Publication Date

7-1-2003

Abstract

In situ hybridization with specific oligonucleotide probes was used to monitor enrichment cultures of yet uncultured populations of sulfate-reducing and small-celled purple sulfur bacteria found to associate into aggregates in the chemocline of meromictic Lake Cadagno, Switzerland, and to select potential isolates. Enrichment and isolation conditions resembled those of their nearest cultured relatives, the sulfate-reducing bacterium Desulfocapsa thiozymogenes and small-celled purple sulfur bacteria belonging to the genus Lamprocystis, respectively. Based on comparative 16S rRNA analysis and physiological characterization, isolate Cad626 was found to resemble D. thiozymogenes although it differed from the type strain by its ability to grow on lactate and pyruvate. Like D. thiozymogenes, isolate Cad626 was able to disproportionate inorganic sulfur compounds (sulfur, thiosulfate, sulfite) and to grow, although growth on sulfur required a sulfide scavenger (FeOOH). Isolate Cad16 represented small-celled purple sulfur bacteria that belonged to a previously detected, but uncultured population designated F and was related to Lamprocystis purpurea as evidenced by comparative 16S rRNA analysis and the presence of bacteriochlorophyll a and the carotenoid okenone. Mixed cultures of isolates Cad626 and Cad16 resulted in their association in aggregates similar to those observed in the chemocline of Lake Cadagno. Concomitant growth enhancement of both isolates in mixed culture suggested synergistic interactions that presumably resemble a source-sink relationship for sulfide between the sulfate-reducing bacterium growing by sulfur disproportionation and the purple sulfur bacteria acting as biotic scavenger. © 2003 Federation of European Microbiological Societies. Published by Elsevier Science B.V. All rights reserved.

Identifier

0038542838 (Scopus)

Publication Title

FEMS Microbiology Ecology

External Full Text Location

https://doi.org/10.1016/S0168-6496(03)00107-7

ISSN

01686496

First Page

29

Last Page

37

Issue

1

Volume

45

Grant

81IT-59640

Fund Ref

Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung

This document is currently not available here.

Share

COinS