survival in manure under fluctuatin

survival in manure under fluctuating temperatures was generally lower than that under constant temperature (Semenov et al., 2007). Moreover, the reduction in survival of the organism was more pronounced when the amplitude in the temperature oscillations was larger (7 °C) than at smaller amplitudes (4 °C). Temperature increase might constitute greater stress and energy expenditure for the organism than decrease in temperature (Semenov et al., 2007). Moreover, gene expression patterns are probably constantly altered under temperature fluctuations. It was recently shown that the histone-like nucleoid structuring (H-NS) protein in E. coli controls a majority of thermoregulated genes at 37 °C and 23 °C (White-Ziegler and Davis, 2009). Hence, differential gene regulation in E. coli may occur across a broad temperature range, next to the regulations occurring at single temperatures (for example, the optimal growth temperature). The H-NS protein may provide a very efficient mechanism of gene expression control under fluctuating temperatures, but we need to increase our understanding of the relationships, if any, to heat and cold shock proteins.