Nitrification inhibitors (NIs) have been used extensively to reduce nitrogen losses and increase crop nitrogen nutrition. However, information is still scant regarding the influence of NIs on nitrogen transformation, nitrous oxide (N2O) emission and nitrogen utilization in plastic-film-mulched calcareous soil under high frequency drip-fertigated condition. Therefore, a field trial was conducted...

S. typhimurium nit mutants are defective in nitrogen assimilation, despite having normal levels of assimilatory enzymes. Complementation, enzyme assays, and genetic mapping show that nit is nadE. We present evidence that ammonia, not glutamine, is the physiological substrate for eubacterial NAD synthetases and that low activity completely accounts for the mutant phenotype.

A widely studied problem in systems biology is to predict bacterial phenotype from growth conditions, using mechanistic models such as flux balance analysis (FBA). However, the inverse prediction of growth conditions from phenotype is rarely considered. Here we develop a computational framework to carry out this inverse prediction on a computational model of bacterial metabolism. We use FBA to ...

The study was undertaken to analyze the rate of uptake and utilization of various amino acids by Azospirillum brasilense Sp81 (RG) in a basal mineral salts solution under non-nitrogen fixing condition. These amino acids including other nitrogenous compounds were tested for both N- and C-sources. The kinetic constants (Km and Vmax) of uptake of some amino acids (e.g. lysine, arginine, proline, g...

The present study evaluates the interactive effects of protein quality and the ratio of protein to digestible carbohydrate on herbivore performance, various aspects of nutritional homeostasis (feeding and post-ingestive regulation) and food choice. In the first experiment, final-instar caterpillars of generalist-feeding African cotton leafworm Spodoptera littoralis (Boisduval) (Lepidoptera: Noc...

High sugar concentration is more preferred in industrial bioethanol production, as it can increase the amount of ethanol produced by the end of fermentation. However, when high sugar concentration is used in the media, yeast cells are exposed to high osmotic stress, which can affect the fermentation performance. The present experiment aimed to investigate the fermentation performance of the yea...

BACKGROUND Health impacts of poor environmental quality have been identified in studies around the world and in Canada. While many of the studies have identified associations between air pollution and mortality or morbidity, few have focused on the role of health care as a potential moderator of impacts. This study assessed the determinants of health care access and utilization in the context o...