Vaca-González Alonso, Flores-Valdez Mario Alberto, Aceves-Sánchez Michel de Jesús, Camacho-Villegas Tanya Amanda, Pérez-Padilla Nayeli Areli, Burciaga-Flores Mirna, De la Cruz Miguel Ángel, Ares Miguel A, Mora-Montes Héctor Manuel, Bravo-Madrigal Jorge, Gaona-Bernal Jorge, Tamez-Castrellón Alma Karina
Maestría en Microbiología Médica, Departamento de Microbiología y Patología, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Guadalajara, Mexico; Biotecnología Médica y Farmacéutica, Centro de Investigación y Asistencia en Tecnología y Diseño del Estado de Jalisco, A. C., Av. Normalistas 800, Col. Colinas de la Normal, Guadalajara, 44270, Mexico.
Biotecnología Médica y Farmacéutica, Centro de Investigación y Asistencia en Tecnología y Diseño del Estado de Jalisco, A. C., Av. Normalistas 800, Col. Colinas de la Normal, Guadalajara, 44270, Mexico.
Tuberculosis (Edinb). 2020 Dec;125:102005. doi: 10.1016/j.tube.2020.102005. Epub 2020 Oct 1.
Biofilm formed in vitro by mycobacteria has been associated with increased antibiotic tolerance as compared with planktonic cells. Cellulose has been identified as a component of DTT-exposed biofilms formed by M. tuberculosis. The celA1 gene of M. tuberculosis encodes a cellulase, which could affect the formation of biofilm by slow-growing mycobacteria. In this work, the celA1 gene of M. tuberculosis was cloned into the integrative pMV361 plasmid and then transformed into M. bovis BCG Pasteur to produce BCG:celA1, to have celA1 expressed from the strong promoter hsp60. We compared planktonic and biofilm growth, possible presence of CelA1 in whole protein extracts, quantitated biofilm, presence of monosaccharides, and bacillary burden in lungs after aerosol infection in BALB/c mice. Differences in the appearance of the surface pellicle and of the biofilm attached to the substrate were observed. In biofilms, we observed a significant decrease of glucosamine in BCG:celA1 compared with BCG:pMV361. Finally, BCG:celA1 had lower viable bacteria than the BCG:pMV361 strain after 24 h and 3 weeks post-infection, but no difference was found at 9 weeks post-infection.
与浮游细胞相比，分枝杆菌在体外形成的生物膜与抗生素耐受性增加有关。纤维素已被确定为结核分枝杆菌形成的经二硫苏糖醇处理的生物膜的一种成分。结核分枝杆菌的celA1基因编码一种纤维素酶，它可能会影响生长缓慢的分枝杆菌生物膜的形成。在这项研究中，结核分枝杆菌的celA1基因被克隆到整合型pMV361质粒中，然后转化到牛分枝杆菌卡介苗巴斯德菌株中，以产生卡介苗：celA1，使celA1在强启动子hsp60的作用下表达。我们比较了浮游生长和生物膜生长情况、全蛋白提取物中是否可能存在CelA1、对生物膜进行定量、检测单糖的存在情况以及BALB/c小鼠气溶胶感染后肺部的细菌负荷。观察到表面菌膜和附着在底物上的生物膜外观存在差异。在生物膜中，我们观察到与卡介苗：pMV361相比，卡介苗：celA1中的氨基葡萄糖显著减少。最后，感染后24小时和3周时，卡介苗：celA1的活菌数量低于卡介苗：pMV361菌株，但在感染后9周时未发现差异。
