Feb 20, 2014 · 15 NH + 4 ammonia oxidation. Nitrification rate measurements were performed at four depths at station M0 (0, 5, 10, 20 m) and at 10-m depth at all other stations. For each set of incubations, 800 ml of water was spiked with 15 N-labelled NH 4 Cl to a nominal final concentration of 750 nmol l 1.The spiked whole water was then split into duplicate 280-ml polycarbonate incubation bottles Effects of estuarine sediment hypoxia on nitrogen fluxes
- IntroductionMaterials and MethodsResultsDiscussionConclusionsAcknowledgementsAnoxic and hypoxic events can adversely affect nutrient cycling in estuarine sediments. Rapid changes in oxygen conditions are not uncommon as net production of oxygen by plants and algae during the daytime and consumption at night can lead to strong diurnal cycling (Engleet al.,1999). Such cycles can interact with already decreased oxygen concentrations to drive bottom waters into short pulses of hypoxia. The incidence of hypoxia in coastal waters and estuaries has increased in response to anthropogenic nutriReverse-transcriptional gene eion of anammox and Sep 29, 2013 · The relative gene eion of hydrazine oxidoreductase encoding gene (hzo) for anaerobic ammonium oxidizing bacteria (anammox) and ammonia monooxygenase encoding gene (amoA) for both ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) in Sanjiang Plain soybean and rice paddy soils of Northeast China was investigated by using real-time reverse-transcriptional
Jan 24, 2014 · Recent evidence from several environments suggest that besides autotrophic ammonia-oxidizing bacteria (AOB), ammonia-oxidizing archaea (AOA) are also able to perform the oxidation of NH 4 + to NO 2 , although the relative importance of AOA in nitrification, compared to AOB, and their differential susceptibility to inhibitory compounds remains unclear. Experimental microcosms were set Growth, activity and temperature responses of ammonia sidered to be responsible for ammonia oxidation, a role for archaea has been suggested by data from metagenomicstudiesandbytheisolationofamarine, autotrophic, ammonia-oxidizing, non-thermophilic crenarchaeon. Evidence for ammonia oxidation by non-thermophilic crenarchaea in marine and terres-trial environments is largely based on abundance of RESPONSES OF AMMONIA-OXIDIZING BACTERIA AND RESPONSES OF AMMONIA-OXIDIZING BACTERIA AND ARCHAEA TO SOIL transcriptional activity of AOB was not detectable, compared to AOA transcript levels, which were higher at 18C than at 28C. Further, a correlation Chapter 3 Responses of archaeal and bacterial ammonia oxidizers in
Jan 20, 2012 · Treusch et al. (2005) demonstrated that besides bacteria members of the Crenarchaeota phylum within the archaea domain also possess amoA homologues, potentially enabling them to perform ammonia oxidation. Archaeal ammonia oxidizers are ubiquitous, appeared to thrive under a wide range of growth conditions (Erguder et al., 2009) and in many soils dominate in number over their Responses of bacterial and archaeal ammonia oxidizers to Jul 01, 2010 · Others have shown that changes in the transcriptional activity of archaeal ammonia oxidizers were correlated to nitrification activity and that only archaeal ammonia oxidizers grew during active nitrification (Tourna et al., 2008, Offre et al., 2009). Stress response of a marine ammonia-oxidizing archaeon Oct 20, 2017 · Nakagawa T, Stahl DA . (2013). Transcriptional response of the archaeal ammonia oxidizer Nitrosopumilus maritimus to low and environmentally relevant ammonia concentrations.
We examined transcription of selected genes for anabolic functions (CO 2 fixation, ammonia transport, and cell wall synthesis) and a central catabolic function (ammonia oxidation) in the thaumarchaeon Nitrosopumilus maritimus SCM1 growing at two ammonia concentrations, as measured by combined ammonia and ammonium, one well above the K m for ammonia oxidation (~500 M) and the other well below the K m (<10 nM). Transcript