Egami's hypothesis that oxygen respiration evolved from nitrate respiration, and this from nitrate fermentation, is not accepted. The reasons are: (1) Presumably there was no nitrate before O2 in the biosphere. (2) On mechanistic grounds, respiration (oxidative phosphorylation) is to be derived directly from photosynthesis (photosynthetic phosphorylation) rather than from any form of fermentation.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1007/BF00927982 | DOI Listing |
Appl Environ Microbiol
January 2025
School of Marine Science and Policy, University of Delaware, Lewes, Delaware, USA.
Unlabelled: Fish gut microbial communities are important for the breakdown and energy harvesting of the host diet. Microbes within the fish gut are selected by environmental and evolutionary factors. To understand how fish gut microbial communities are shaped by diet, three tropical fish species (hawkfish, ; yellow tang, ; and triggerfish, ) were fed piscivorous (fish meal pellets), herbivorous (seaweed), and invertivorous (shrimp) diets, respectively.
View Article and Find Full Text PDFJ Environ Manage
January 2025
Key Laboratory of Water Environment Evolution and Pollution Control in the Three Gorges Reservoir, Chongqing Three Georges University, Chongqing, 404100, PR China.
Nitrogen and phosphorus depositions and global warming have continuously intensified, impacting soil respiration. However, the response mechanisms of soil respiration rate (R) and its temperature sensitivity (Q) to nitrogen and phosphorus depositions are still unclear, especially for riparian zones. Intact Fluvisols were collected at different water-level elevations (150, 160, 170, and 180 m) of the riparian zone of the Three Gorges Reservoir, China and incubated under 20 and 30 °C with additions of nitrogen (36 kg N ha yr), phosphorus (0.
View Article and Find Full Text PDFACS Omega
January 2025
Birmingham Institute of Forest Research (BIFoR), University of Birmingham, Edgbaston B15 2TT, U.K.
In the future, with elevated atmospheric CO (eCO), forests are expected to increase woody biomass to capture more carbon (C), though this is dependent on soil nutrient availability. While young forests may access unused nutrients by growing into an unexplored soil environment, it is unclear how or if mature forests can adapt belowground under eCO. Soil respiration ( ) and nutrient bioavailability are integrative ecosystem measures of below-ground dynamics.
View Article and Find Full Text PDFPlant Sci
January 2025
UMR INRAE 1355, Université Nice Côte d'Azur, Institut Sophia Agrobiotech, 06903 Sophia Antipolis, France. Electronic address:
Flooding induces hypoxia in plant tissues, impacting various physiological and biochemical processes. This study investigates the adaptive response of the roots and nitrogen-fixing nodules of Medicago truncatula in symbiosis with Sinorhizobium meliloti under short-term hypoxia caused by flooding. Four-week-old plants were subjected to flooding for 1 to 4 days.
View Article and Find Full Text PDFUnlabelled: The intestinal diarrheal pathogen colonizes the host terminal ileum, a microaerophilic, glucose-poor, nitrate-rich environment. In this environment, respires nitrate and increases transport and utilization of alternative carbon sources via the cAMP receptor protein (CRP), a transcription factor that is active during glucose scarcity. Here we show that nitrate respiration in aerated cultures is under control of CRP and, therefore, glucose availability.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!