RRC ID 56346
著者 Tsuchiya K, Cao YY, Kurokawa M, Ashino K, Yomo T, Ying BW.
タイトル A decay effect of the growth rate associated with genome reduction in Escherichia coli.
ジャーナル BMC Microbiol
Abstract BACKGROUND:Bacterial growth is an important topic in microbiology and of crucial importance to better understand living cells. Bacterial growth dynamics are quantitatively examined using various methods to determine the physical, chemical or biological features of growing populations. Due to methodological differences, the exponential growth rate, which is a parameter that is representative of growth dynamics, should be differentiated. Ignoring such differentiation in the growth analysis might overlook somehow slight but significant changes in cellular features of the growing population. Both experimental and theoretical investigations are required to address these issues.
RESULTS:This study experimentally verified the differentiation in growth rates attributed to different methodologies, and demonstrated that the most popular method, optical turbidity, led to the determination of a lower growth rate in comparison to the methods based on colony formation and cellular adenosine triphosphate, due to a decay effect of reading OD600 during a population increase. Accordingly, the logistic model, which is commonly applied to the high-throughput growth data reading the OD600, was revised by introducing a new parameter: the decay rate, to compensate for the lowered estimation in growth rates. An improved goodness of fit in comparison to the original model was acquired due to this revision. Applying the modified logistic model to hundreds of growth data acquired from an assortment of Escherichia coli strains carrying the reduced genomes led to an intriguing finding of a correlation between the decay rate and the genome size. The decay effect seemed to be partially attributed to the decrease in cell size accompanied by a population increase and was medium dependent.
CONCLUSIONS:The present study provides not only an improved theoretical tool for the high-throughput studies on bacterial growth dynamics linking with optical turbidity to biological meaning, but also a novel insight of the genome reduction correlated decay effect, which potentially reflects the changing cellular features during population increase. It is valuable for understanding the genome evolution and the fitness increase in microbial life.
巻・号 18(1)
ページ 101
公開日 2018-9-3
DOI 10.1186/s12866-018-1242-4
PII 10.1186/s12866-018-1242-4
PMID 30176803
PMC PMC6122737
MeSH Cell Culture Techniques Colony Count, Microbial Escherichia coli / cytology Escherichia coli / genetics* Escherichia coli / growth & development* Genome Size* Genome, Bacterial Models, Biological
IF 3.287
引用数 1
リソース情報
原核生物(大腸菌) ME9801