Grupo de Microbiología Clínica y Ambiental, Facultad de Ciencias Exactas y Naturales, Programa de Biología, Universidad de Cartagena, Campus San Pablo, Cartagena 130015, Colombia.
Grupo de Investigación CIPTEC, Facultad de Ingeniería, Programa de Ingeniería de Procesos, Fundación Universitaria Tecnológico Comfenalco, Cartagena 130015, Colombia.
Molecules. 2018 Feb 13;23(2):406. doi: 10.3390/molecules23020406.
An Gram negative strain of , indigenous to environments contaminated by Cr(VI) and identified by biochemical methods and 16S rRNA gene analysis, reduced chromate by 100%, 98-99% and 92% at concentrations in the 10-70, 80-300, and 500 mg/L range, respectively at pH 7 and temperature 37 °C. Increasing concentrations of Cr(VI) in the medium lowered the growth rate but could not be directly correlated with the amount of Cr(VI) reduced. The strain also exhibited multiple resistance to antibiotics and tolerance and resistance to various heavy metals (Ni, Zn and Cu), with the exception of Hg. Hexavalent chromium reduction was mainly associated with the soluble fraction of the cell evaluated with crude cell-free extracts. A protein of molecular weight around 25 kDa was detected on SDS-PAGE gel depending on the concentration of hexavalent chromium in the medium (0, 100 and 500 mg/L). In silico analysis in this contribution, revealed the presence of the chromate reductase gene in , evidenced through a fragment of around 468 bp obtained experimentally. High Cr(VI) concentration resistance and high Cr(VI) reducing ability of the strain make it a suitable candidate for bioremediation.
一株革兰氏阴性菌，栖息于受六价铬污染的环境中，通过生化方法和 16S rRNA 基因分析进行鉴定，在 pH 值为 7 和 37°C 的温度下，分别在 10-70、80-300 和 500mg/L 的浓度范围内将铬酸盐还原 100%、98-99%和 92%。培养基中六价铬浓度的增加降低了生长速率，但不能直接与还原的六价铬量相关联。该菌株还表现出对多种抗生素的多重耐药性以及对各种重金属（Ni、Zn 和 Cu）的耐受性和抗性，除了 Hg 以外。六价铬的还原主要与用粗细胞提取物评估的细胞可溶性部分有关。根据培养基中六价铬的浓度（0、100 和 500mg/L），在 SDS-PAGE 凝胶上检测到分子量约为 25kDa 的蛋白质。本研究中的计算机分析显示， 中存在铬酸盐还原酶基因 ，这是通过实验获得的约 468bp 的片段证明的。该菌株对高浓度六价铬的抗性和高六价铬还原能力使其成为生物修复的合适候选者。
