Scully Sean M, Iloranta Pia, Myllymaki Pauli, Orlygsson Johann
Faculty of Natural Resource Sciences, University of Akureyri, Nordurslod 2, Borgir, 600, Akureyri, Iceland.
Extremophiles. 2015 Jul;19(4):809-18. doi: 10.1007/s00792-015-0756-z. Epub 2015 May 22.
Fifty-six thermophilic strains including members of Caldanaerobacter, Caldicellulosiruptor, Caloramator, Clostridium, Thermoanaerobacter, and Thermoanaerobacterium, were investigated for branched-chain amino acid degradation in the presence of thiosulfate in batch culture. All of the Thermoanaerobacter and Caldanaerobacter strains (24) degraded the branched-chain amino acids (leucine, isoleucine, and valine) to a mixture of their corresponding branched-chain fatty acids and branched-chain alcohols. Only one Caloramator strain degraded the branched-chain amino acids to the corresponding branched-chain fatty acids. The ratio of branched-chain fatty acid production over branched-chain alcohol production for Thermoanaerobacter was 7.15, 6.61, and 11.53 for leucine, isoleucine, and valine, respectively. These values for Caldanaerobacter were 3.49, 4.13, and 7.31, respectively. This indicates that members within Caldanaerobacter produce proportionally more of the alcohols as compared with Thermoanaerobacter. No species within other genera investigated produced branched-chain alcohols from branched-chain amino acids in the presence of thiosulfate.
对56株嗜热菌株进行了研究，这些菌株包括卡尔丹厌氧杆菌属、嗜热纤维梭菌属、热聚生孢杆菌属、梭菌属、嗜热厌氧杆菌属和嗜热厌氧芽孢杆菌属的成员，在分批培养中，于硫代硫酸盐存在的情况下研究它们对支链氨基酸的降解情况。所有嗜热厌氧杆菌属和卡尔丹厌氧杆菌属菌株（共24株）都将支链氨基酸（亮氨酸、异亮氨酸和缬氨酸）降解为相应的支链脂肪酸和支链醇的混合物。只有一株热聚生孢杆菌属菌株将支链氨基酸降解为相应的支链脂肪酸。嗜热厌氧杆菌属菌株中，亮氨酸、异亮氨酸和缬氨酸产生支链脂肪酸与产生支链醇的比例分别为7.15、6.61和11.53。卡尔丹厌氧杆菌属菌株的这些比例分别为3.49、4.13和7.31。这表明与嗜热厌氧杆菌属相比，卡尔丹厌氧杆菌属成员产生的醇类比例更高。在所研究的其他属中，没有物种在硫代硫酸盐存在的情况下从支链氨基酸产生支链醇。
