Maximum specific growth rate of anammox bacteria revisited

WATER RESEARCH

卷:116

Article

Zhang, Lei¹  Narita, Yuko¹  Gao, Lin¹  Ali, Muhammad^1,2  Oshiki, Mamoru³  Okabe, Satoshi¹ 

[1] Hokkaido Univ, Div Environm Engn, Fac Engn, North 13,West 8, Sapporo, Hokkaido 0608628, Japan

[2] KAUST, Biol & Environm Sci & Engn BESE Div, WDRC, Thuwal, Saudi Arabia

[3] Nagaoka Natl Coll Technol, Dept Civil Engn, 888 Nishikatakaimachi, Nagaoka, Niigata 9400834, Japan

关键词: Anammox bacteria;    Maximum specific growth rate;    16S rRNA genes;    Planktonic cells;    PVA-SA immobilized cells;   

DOI  :  10.1016/j.watres.2017.03.027

来源: Elsevier

【 摘 要 】

Anammox bacteria have long been considered to be slow-growing bacteria. However, it has recently been reported that they could grow much faster than previously thought when they were cultivated in a membrane bioreactor (MBR) with a step-wise decrease in the solid retention time (SRT). Here, we reevaluated the maximum specific growth rates (mu(max)) of three phylogenetically distant anammox bacterial species (i.e. Ca. Brocadia sinica, Ca. Jettenia caeni and Ca. Scalindua sp.) by directly measuring 16S rRNA gene copy numbers using newly developed quantitative polymerase chain reaction (qPCR) assays. When free-living planktonic Ca. B. sinica and Ca. J. caeni cells were immobilized in polyvinyl alcohol (PVA) and sodium alginate (SA) gel beads and cultivated in an up-flow column reactor with high substrate loading rates at 37 degrees C, the mu(max) were determined to be 033 +/- 0.02 d(-1) and 0.18 d(-1) (corresponding doubling time of 2.1 day and 3.9 day) from the exponential increases in 16S rRNA genes copy numbers, respectively. These values were faster than the fastest growth rates reported for these species so far. The cultivation of anammox bacteria in gel beads was achieved less than one month without special cultivation method and selection pressure, and the exponential increase in 16S rRNA gene numbers was directly measured by qPCR with high reproducibility; therefore, the resulting mu(max) values were considered accurate. Taken together, the fast growth is, therefore, considered to be an intrinsic kinetic property of anammox bacteria. (C) 2017 Elsevier Ltd. All rights reserved.

【 授权许可】

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