当前位置： SCI文献检索 > Frontiers in Microbiology期刊下所有文献 > Concurrent activity of anammox and denitrifying bacteria in the Black Sea.

Concurrent activity of anammox and denitrifying bacteria in the Black Sea.

Abstract：

:After the discovery of ANaerobic AMMonium OXidation (anammox) in the environment, the role of heterotrophic denitrification as the main marine pathway for fixed N loss has been questioned. A 3 part, 15 month time series investigating nitrite reductase (nirS) mRNA transcripts at a single location in the Black Sea was conducted in order to better understand the activity of anammox and denitrifying bacteria. Here we show that both of these groups were active, as well as being concurrent in the lower suboxic zone over this time span. Their distributions, however, differed in that only expression of denitrification-type nirS was seen in the upper suboxic zone, where geochemistry was variable. Depth profiles covering the suboxic zone showed that the four groups of anammox-type sequences were expressed consistently in the lower suboxic zone, and were consistent with anammox 16 S rDNA gene profiles. By contrast, denitrifier-type nirS sequence groups were mixed; some groups exhibited consistent expression in the lower suboxic zone, while others appeared less consistent. Co-occurrence of both anammox and denitrifier expression was common and ongoing. Both types of transcripts were also found in samples with low concentrations of sulfide (>2 μM). Six major groups of denitrifier-type nirS transcripts were identified, and several groups of denitrifier-type nirS transcripts were closely related to sequences from the Baltic Sea. An increase in denitrifier-type nirS transcript diversity and depth range in October 2007 corresponded to a small increase in mixed layer net community productivity (NCP) as measured by O(2)/Ar gas ratios, as well as to an increase in N(2) concentrations in the suboxic zone. Taken together, the variations in expression patterns between anammox and denitrification provide one possible explanation as to how near instantaneous rate measurements, such as isotope spike experiments, may regularly detect anammox activity but underreport denitrification.

journal_name

Front Microbiol

journal_title

Frontiers in microbiology

authors

Kirkpatrick JB,Fuchsman CA,Yakushev E,Staley JT,Murray JW

doi

10.3389/fmicb.2012.00256

subject

Has Abstract

pub_date

2012-07-19 00:00:00

pages

256

issn

1664-302X

journal_volume

pub_type

杂志文章

在线工具

Concurrent activity of anammox and denitrifying bacteria in the Black Sea.