Normand P, Simonet P, Bardin R
Centre de Recherche en Biologie Forestière, Université Laval, Québec, Canada.
Mol Gen Genet. 1988 Aug;213(2-3):238-46. doi: 10.1007/BF00339587.
Southern blots of Frankia total DNAs were hybridized with nifHDK probes from Rhizobium meliloti, Klebsiella pneumoniae and Frankia strain Arl3. Differences between strains were noted in the size of the hybridizing restriction fragments. These differences were more pronounced among Elaeagnus-compatible strains than among Alnus- or Casuarina-compatible strains. Gene banks constructed for Frankia strains EUN1f, HRN18a, CeD and ACoN24d were used to isolate nif-hybridizing restriction fragments for subsequent mapping and comparisons. The nifH zone had the highest sequence conservation and the nifH and nifD genes were found to be contiguous. The complete nucleotide sequence of the nifH open reading frame (ORF) from Frankia strain Arl3 is 861 bp in length and encodes a polypeptide of 287 amino acids. Comparisons of these nucleic acid and amino acid sequences with other published nifH sequences suggest that Frankia is most similar to Anabaena and Azotobacter spp. and K. pneumoniae and least similar to the Gram-positive Clostridium pasteurianum and to the archaebacterium Methanococcus voltae.
用来自苜蓿根瘤菌、肺炎克雷伯菌和Frankia菌株Arl3的nifHDK探针与Frankia总DNA的Southern印迹杂交。在杂交限制性片段的大小上注意到菌株之间的差异。这些差异在与胡颓子属植物相容的菌株中比在与桤木属或木麻黄属植物相容的菌株中更明显。为Frankia菌株EUN1f、HRN18a、CeD和ACoN24d构建的基因文库用于分离nif杂交限制性片段，以便随后进行图谱绘制和比较。nifH区域具有最高的序列保守性，并且发现nifH和nifD基因是相邻的。Frankia菌株Arl3的nifH开放阅读框（ORF）的完整核苷酸序列长度为861 bp，编码一个由287个氨基酸组成的多肽。将这些核酸和氨基酸序列与其他已发表的nifH序列进行比较表明，Frankia与鱼腥藻属和固氮菌属以及肺炎克雷伯菌最相似，与革兰氏阳性的巴氏梭菌和古细菌沃氏甲烷球菌最不相似。
