Sánchez Borja, Champomier-Vergès Marie-Christine, Stuer-Lauridsen Birgitte, Ruas-Madiedo Patricia, Anglade Patricia, Baraige Fabienne, de los Reyes-Gavilán Clara G, Johansen Eric, Zagorec Monique, Margolles Abelardo
Unité Flore Lactique et Environnement Carné (UR309), INRA, Domaine de Vilvert, F-78350 Jouy-en-Josas, France.
Appl Environ Microbiol. 2007 Nov;73(21):6757-67. doi: 10.1128/AEM.00637-07. Epub 2007 Sep 7.
Bile salts are natural detergents that facilitate the digestion and absorption of the hydrophobic components of the diet. However, their amphiphilic nature makes them very inhibitory for bacteria and strongly influences bacterial survival in the gastrointestinal tract. Adaptation to and tolerance of bile stress is therefore crucial for the persistence of bacteria in the human colonic niche. Bifidobacterium animalis subsp. lactis, a probiotic bacterium with documented health benefits, is applied largely in fermented dairy products. In this study, the effect of bile salts on proteomes of B. animalis subsp. lactis IPLA 4549 and its bile-resistant derivative B. animalis subsp. lactis 4549dOx was analyzed, leading to the identification of proteins which may represent the targets of bile salt response and adaptation in B. animalis subsp. lactis. The comparison of the wild-type and the bile-resistant strain responses allowed us to hypothesize about the resistance mechanisms acquired by the derivative resistant strain and about the bile salt response in B. animalis subsp. lactis. In addition, significant differences in the levels of metabolic end products of the bifid shunt and in the redox status of the cells were also detected, which correlate with some differences observed between the proteomes. These results indicate that adaptation and response to bile in B. animalis subsp. lactis involve several physiological mechanisms that are jointly dedicated to reduce the deleterious impact of bile on the cell's physiology.
胆汁盐是天然洗涤剂，有助于饮食中疏水性成分的消化和吸收。然而，它们的两亲性使其对细菌具有很强的抑制作用，并强烈影响细菌在胃肠道中的存活。因此，适应和耐受胆汁压力对于细菌在人类结肠生态位中的持续存在至关重要。动物双歧杆菌乳酸亚种是一种具有已证实健康益处的益生菌，广泛应用于发酵乳制品中。在本研究中，分析了胆汁盐对动物双歧杆菌乳酸亚种IPLA 4549及其胆汁抗性衍生物动物双歧杆菌乳酸亚种4549dOx蛋白质组的影响，从而鉴定出可能代表动物双歧杆菌乳酸亚种中胆汁盐反应和适应靶点的蛋白质。野生型和胆汁抗性菌株反应的比较使我们能够推测衍生抗性菌株获得的抗性机制以及动物双歧杆菌乳酸亚种中的胆汁盐反应。此外，还检测到双歧分流代谢终产物水平和细胞氧化还原状态的显著差异，这与蛋白质组之间观察到的一些差异相关。这些结果表明，动物双歧杆菌乳酸亚种对胆汁的适应和反应涉及多种生理机制，这些机制共同致力于减少胆汁对细胞生理的有害影响。
