%0 Journal Article
%T Breeding of ammonium-tolerant mutants of Actinobacillus succinogenes for succinic acid production and effect of ammonium<br>耐铵型产琥珀酸放线杆菌的选育及铵离子对其生长代谢的影响
%A Guizi Ye
%A Min Jiang
%A Kequan Chen
%A Jian Li
%A Yonglan Xi
%A Xiumei Huang
%A Ping Wei
%A <br>叶贵子
%A 姜岷
%A 陈可泉
%A 李建
%A 奚永兰
%A 黄秀梅
%A 韦萍
%J 生物工程学报
%D 2010
%I 
%X An ammonium-tolerant mutant of Actinobacillus succinogenes, YZ25, was obtained in the medium containing 61?242 mmol/L NH4+ after DES mutagenesis. Succinic acid produced by the mutant YZ25 reached 32.68 g/L when the medium contains 50 g/L glucose and 121 mmol/L ammonium, which was increased by 180.5% compared with that of the parent strain. The effects of different ammonium salts on the growth of the mutant and its metabolic response to high ammonium concentrations were investigated. The results showed that low ammonium concentration could improve the specific growth rates of the mutants, while high ammonium concentration inhibited cell growth. The ammonia-nitrogen half-inhibition constants (Ki) for different ammonium salts were as follows: 215 mmol/L for (NH4)2SO4, 265 mmol/L for NH4HCO3, 235 mmol/L for NH4Cl, and 210 mmol/L for NH4NO3. The process of ammonium inhibition on the mutant YZ25 was investigated in 3.0 L stirred fermentor. When NH4OH was used to buffer the pH, cell growth was not inhibited. However, production of succinic acid and consumption of glucose gradually decreased when cells entered the stationary phase, and the glucose could not be utilized completely at the end of fermentation. The possible ammonium inhibition mechanism was discussed based on the metabolic pathway of A. succinogenes.
%K succinic acid
%K breeding
%K ammonium-tolerant
%K Actinobacillus succinogenes
%K inhibition mechanism<br>琥珀酸，选育，耐铵离子，产琥珀酸放线杆菌，抑制机理
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=90BA3D13E7F3BC869AC96FB3DA594E3FE34FBF7B8BC0E591&jid=A66E90C274451689E69F6F0291467824&aid=7E1CA17AFF6978EEC4841A844FFFCBED&yid=140ECF96957D60B2&vid=96C778EE049EE47D&iid=0B39A22176CE99FB&sid=DD74772618543076&eid=847B14427F4BF76A&journal_id=1000-3061&journal_name=生物工程学报&referenced_num=1&reference_num=0