Chamkha Mohamed, Record Eric, Garcia Jean-Louis, Asther Marcel, Labat Marc
Laboratoire de Microbiologie IRD,IFR-BAIM, Universités de Provence et de la Méditerranée, ESIL case 925, 163 Avenue de Luminy, 13288 Marseille Cedex 9, France.
Curr Microbiol. 2002 May;44(5):341-9. doi: 10.1007/s00284-001-0020-x.
A facultatively anaerobic, mesophilic, Gram-negative, non-motile, non-sporulated bacterium, designated strain C2, was isolated from an anaerobic digester fed with shea cake rich in tannins and aromatic compounds and previously inoculated with anaerobic sludge from the pit of a slaughterhouse, after enrichment on tannic acid. The straight rods occurred singly or in pairs. Strain C2 fermented numerous carbohydrates (fructose, galactose, glucose, lactose, mannose, maltose, melibiose, raffinose, rhamnose, ribose, saccharose, sorbitol, trehalose, and xylose) and peptides (Biotrypcase, Casamino acids, and yeast extract), producing acid and gas, and had a G + C content of 51.6 +/- 0.1 mol %. Strain C2 was very closely related to Escherichia coli (= DSM 30083(T)) phylogenetically (similarity of 99%), genotypically (DNA homology of 79%), and phenotypically. The isolate tolerated tannic acid (hydrolyzable tannin) and decarboxylated by non-oxidative decarboxylation only p-hydroxybenzoic and vanillic acids to their corresponding phenol and guaicol, under anaerobic and aerobic conditions without further degradation. Adding glucose increased growth and the rate of conversion. High concentrations of p-hydroxybenzoic acid or vanillic acid inhibited growth, and decarboxylation could not occur completely, suggesting phenol toxicity. In contrast, the type strain of E. coli cannot metabolize p-hydroxybenzoic and vanillic acids, anaerobically or aerobically, with or without glucose added.
从一个以富含单宁和芳香化合物的乳木果饼为原料且预先接种了屠宰场坑内厌氧污泥的厌氧消化池中，经单宁酸富集培养后，分离出一株兼性厌氧、嗜温、革兰氏阴性、无运动性、不产芽孢的细菌，命名为菌株C2。该菌呈直杆状，单个或成对出现。菌株C2能发酵多种碳水化合物（果糖、半乳糖、葡萄糖、乳糖、甘露糖、麦芽糖、蜜二糖、棉子糖、鼠李糖、核糖、蔗糖、山梨醇、海藻糖和木糖）和肽（胰蛋白胨、酪蛋白氨基酸和酵母提取物），产酸产气，其G + C含量为51.6±0.1 mol%。菌株C2在系统发育上（相似度99%）、基因型上（DNA同源性79%）和表型上与大肠杆菌（= DSM 30083(T)）密切相关。该分离株能耐受单宁酸（可水解单宁），在厌氧和好氧条件下，仅通过非氧化脱羧作用将对羟基苯甲酸和香草酸分别脱羧为相应的苯酚和愈创木酚，且不会进一步降解。添加葡萄糖可促进生长并提高转化速率。高浓度的对羟基苯甲酸或香草酸会抑制生长，且脱羧反应不能完全发生，表明存在酚类毒性。相比之下，大肠杆菌模式菌株无论在厌氧还是好氧条件下，添加或不添加葡萄糖，都不能代谢对羟基苯甲酸和香草酸。
