Departamento de Ciência de Alimentos-FEA, Universidade Estadual de Campinas-UNICAMP, Rua Monteiro Lobato, 80 CEP, Campinas, SP 13083-862, Brazil.
Biodegradation. 2013 Sep;24(5):699-709. doi: 10.1007/s10532-012-9617-y. Epub 2013 Jan 5.
Phenol is a toxic aromatic compound used or produced in many industries and as a result a common component of industrial wastewaters. Phenol containing waste streams are frequently hypersaline and therefore require halophilic microorganisms for efficient biotreatment without dilution. In this study three halophilic bacteria isolated from different saline environments and identified as Halomonas organivorans, Arhodomonas aquaeolei and Modicisalibacter tunisiensis were shown to be able to grow on phenol in hypersaline media containing 100 g/L of total salts at a concentration of 3 mM (280 mg/L), well above the concentration found in most waste streams. Genes encoding the aromatic dioxygenase enzymes catechol 1,2 dioxygenase and protocatechuate 3,4-dioxygenase were present in all strains as determined by PCR amplification using primers specific for highly conserved regions of the genes. The gene for protocatechuate 3,4-dioxygenase was cloned from the isolated H. organivorans and the translated protein was evaluated by comparative protein sequence analysis with protocatechuate 3,4-dioxygenase proteins from other microorganisms. Although the analysis revealed a wide range of sequence divergence among the protocatechuate 3,4-dioxygenase family, all of the conserved domain amino acid structures identified for this enzyme family are identical or conservatively substituted in the H. organivorans enzyme.
苯酚是一种有毒的芳香族化合物，广泛应用于许多工业领域，也是工业废水中常见的成分。含有苯酚的废水通常盐分很高，因此需要嗜盐微生物进行高效的生物处理，而无需稀释。在这项研究中，从不同盐环境中分离到的三种嗜盐细菌被鉴定为盐单胞菌（Halomonas organivorans）、水生盐单胞菌（Arhodomonas aquaeolei）和突尼斯盐美菌（Modicisalibacter tunisiensis），它们能够在含有 100 g/L 总盐的高盐培养基中以 3 mM（280 mg/L）的浓度生长，远高于大多数废水中的浓度。通过使用针对基因高度保守区域的引物进行 PCR 扩增，确定所有菌株都存在编码芳香族双加氧酶酶儿茶酚 1,2-双加氧酶和原儿茶酸 3,4-双加氧酶的基因。从分离到的 H. organivorans 中克隆了原儿茶酸 3,4-双加氧酶基因，并通过与其他微生物中原儿茶酸 3,4-双加氧酶蛋白的比较蛋白质序列分析评估了翻译后的蛋白。尽管分析表明原儿茶酸 3,4-双加氧酶家族之间存在广泛的序列差异，但该酶家族所有保守结构域的氨基酸结构在 H. organivorans 酶中都是相同的或保守取代的。
