Bacteria monitoring

How does a bacterial cell sense a gradient of a chemotactic stimulus Does it compare the stimulant concentrations between both ends of the cell or does it make the comparison between two consecutive time points In other words, do bacteria monitor a spatial or a temporal gradient In an elegant study, Macnab and Koshland [451] demonstrated... 

Gariity, L.F. and Ordal, G.W. (1995). Chemotaxis in Bacillus subtilis how bacteria monitor environmental signals. Pharmacol. Ther. 68, 87—104. 

Wang, L. Zhao, W O Donoghue, M. B. Tan, W. Fluorescent nanoparticles for multiplexed bacteria monitoring. Bioconjugate Chem. 2007,18, 297-301. 

Corrosion Control Engineering Joint Venture, Task Group EI/1, Review of Current Practices for Monitoring Bacteria Growth in Oilfield Systems, ICorr Document 001/87 (1987). 

The non-penicillin wastewater from a pharmaceutical company was collected and used in the batch aeration wastewater treatment experiment. The pharmaceutical wastewater had a clear orange colour, strong odour, contained toxic chemicals and had a COD value in the range of 3000-30,000 mg per litre. The pH of the wastewater was neutralised and monitored for each experimental ran, as the bacteria would have a higher rate of propagation at neutral pH. 

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