Microbial utilization of thiosulfate in the deep sea’

• Main Authors: Jon Ii. Tuttle, Holger W. Jannusch
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: North Atlantic
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.553.9430; http://www.aslo.org/lo/toc/vol_21/issue_5/0697.pdf

Natural microbial populations in deep and shallow North Atlantic water and previously isolated heterotrophic thiosulfate-oxidizing bacteria have the potential to metabolize thio-sulfate when incubated in situ at elevated hydrostatic pressure and low tcmpernture. The fact that sulfate is the second most abundant anion in seawater (about 0.03 M as Na2S0,) has led to the assumption that sulfur-metabolizing bacteria play a signifi-cant role in the transformations of organic and inorganic carbon in the marine envi-ronment. The importance of obligately an-aerobic sulfate-reducing bacteria in marine sulfur turnover is generally accepted, but the aerobic portion of the marine microbial sulfur cycle in offshore water is not well understood. Studies on marine microbial sulfur oxidation (Tilton et al. 1967; Adair and Gunderscn 1969) have focused mainly on the distribution of Thiobacillus sp. in the marine environment and were based on the assumptions that the microbial oxida-tion of reduced sulfur compounds in the sea is carried out by chemolithotrophic mi-croorganisms similar to those found in ter-restrial environments and that anaerobic photosynthetic sulfur-oxidizing bacteria are absent from aerobic offshore ocean wa-ters or anoxic zones (e.g. the Black Sea and Cariaco Trench) lying beneath the eu-photic zone. Thiobacilli could be found in inshore waters and sediments, but were rarely present in appreciable numbers in offshore waters and sediments or even in the Cariaco Trench (Tilton et al. 1967). Our own studies on the occurrence of colorless, sulfur-oxidizing bacteria in the sea confirmed the general absence of chemoautotrophic Thiohacillus sp., but re-1 SlIpported by grants GA 29665 and DES75-