Rotthauwe J H, de Boer W, Liesack W
Max-Planck-Institut für Terrestrische Mikrobiologie, Marburg, Germany.
FEMS Microbiol Lett. 1995 Nov 1;133(1-2):131-5. doi: 10.1111/j.1574-6968.1995.tb07873.x.
DNA encoding ammonia monooxygenase from two phylogenetically related autotrophic nitrifying bacteria, Nitrosospira sp. AHB1 and Nitrosolobus multiformis C-71, was amplified by PCR. The resulting products were cloned into the vector pCR-Script. A continuous region of DNA of about 1.5 kb for strain AHB1 and 1.24 kb for N. multiformis C-71 was analysed. These comprised the major part of the gene amoA encoding the active site polypeptide and, directly downstream, the 5' portion of the amoB gene. The identity values for these sequences at the amino acid level were 93.0% for amoA and 96.1% for amoB. The corresponding values for the nucleic acid sequences were 86.7% and 88.8%, respectively. The identity of the 16S rRNA gene of strain AHB1 to that of N. multiformis C-71 was at least 98.5%. The different degree of sequence conservation between the 16S rDNA and the genes encoding for ammonia monooxygenase facilitates the application of the latter as a molecular tool for a fine-scale differentiation of autotrophic nitrifying bacteria, at the species or strain level, in both environmental and cultivation studies.
通过聚合酶链式反应（PCR）扩增了来自两种系统发育相关的自养硝化细菌——亚硝化螺旋菌属（Nitrosospira）AHB1菌株和多形亚硝化叶菌（Nitrosolobus multiformis）C - 71菌株的编码氨单加氧酶的DNA。将所得产物克隆到载体pCR - Script中。对AHB1菌株约1.5 kb和多形亚硝化叶菌C - 71菌株1.24 kb的连续DNA区域进行了分析。这些区域包含编码活性位点多肽的amoA基因的主要部分，以及直接位于下游的amoB基因的5'部分。这些序列在氨基酸水平上的同一性值，amoA为93.0%，amoB为96.1%。核酸序列的相应值分别为86.7%和88.8%。AHB1菌株的16S rRNA基因与多形亚硝化叶菌C - 71菌株的16S rRNA基因的同一性至少为98.5%。16S rDNA与编码氨单加氧酶的基因之间不同程度的序列保守性，有助于将后者作为一种分子工具，在环境和培养研究中，在物种或菌株水平上对自养硝化细菌进行精细区分。
