In this study, the enzyme activities and their relationships to domestic wastewater purification are investigated in four different types of subsurface-flow constructed wetlands (CWs), namely the traditional horizontal subsurface-flow, horizontal baffled subsurface-flow, vertical baffled subsurface-flow, and composite baffled subsurface-flow CWs. Results showed that the urease activity in the c...

Title of Document: REGULATION OF ESTUARINE PHYTOPLANKTON AND BACTERIAL UREA UPTAKE AND UREASE ACTIVITY BY ENVIRONMENTAL FACTORS Caroline Miller Solomon, Ph.D., 2006 Directed By: Professor Patricia M. Glibert Marine Estuarine Environmental Science The regulation by environmental factors of two enzymes involved with urea utilization – urea transport and urease – in estuarine phytoplankton and bac...

Proteus mirabilis, a common agent of nosocomially acquired and catheter-associated urinary tract infection, is the most frequent cause of infection-induced bladder and kidney stones. Urease-catalyzed urea hydrolysis initiates stone formation in urine and can be inhibited by acetohydroxamic acid and other structural analogs of urea. Since P. mirabilis urease is inducible with urea, there has bee...

The role in virulence of Actinobacillus pleuropneumoniae urease activity was investigated. A urease-negative mutant was isolated following transposon mutagenesis with a mini-Tn10 derivative. Both the parent strain and the urease-negative mutant exhibited identical LD50 values in a murine infection model. Pig challenge confirmed that the urease-negative mutant was fully virulent, since experimen...

The experiment was conducted to study the effect of treatment of rice straw with urea and a urease containing midden soil on the chemical composition of treated rice straw, feed intake of the animals, nutrients digestibility, body weight gain, feed conversion efficiency and overall economy of feeding for a period of 105 days. Twelve indigenous growing cattle (live weight 130.00±1.67 kg) were se...

As potent allelochemicals, phenolic acids are believed to be associated with replanting disease and cause microflora shift and structural disorder in the rhizosphere soil of continuously monocultured Radix pseudostellariae. The transcriptome sequencing was used to reveal the mechanisms underlying the differential response of pathogenic bacterium Kosakonia sacchari and beneficial bacterium Bacil...

Heavy metal pollution in soil and water has been of worldwide concern due to their biotoxicity/ecotoxicity the ecosystem, accumulation food chain, persistence environment. Microbially induced carbonate precipitation (MICP) is known as an efficient cost-effective biogeochemical process for remediation heavy metals contaminated This study reviews mechanisms biomineralization urease-producing micr...

Atrazine has been extensively used in China’s agricultural production for a long time and the potential risks to environment have received widespread attention. The purpose of this study was examine effect continuous application atrazine on soil herbicide residues, enzyme activity, microbial community structure, as well provide theoretical reference appropriate improvement soil. Previous studie...

Sonication of Ureaplasma urealyticum cells grown in a dialysate growth medium effectively separated the cytoplasmic fraction from the membrane fraction, with both fractions relatively free from exogenous contaminating proteins. The urease activity was associated with the cytoplasmic fraction, and the ureaplasmal urease exhibited a specific activity higher than that of crystalline jack bean urea...