Wasteson Y, Olsvik O
Department of Microbiology and Immunology, Norwegian College of Veterinary Medicine, Oslo.
Zentralbl Veterinarmed B. 1991 Aug;38(6):445-52. doi: 10.1111/j.1439-0450.1991.tb00894.x.
Ten porcine strains of enterotoxigenic Escherichia coli possessing the K88 (F4) adhesion fimbriae, were selected for study of enterotoxin- and fimbriae-encoding plasmids. Plasmid DNA, separated according to size by gel electrophoresis was transferred to nylon membranes by Southern blotting, and hybridized with enzyme-labelled oligonucleotide probes for ST1 and LT1 enterotoxins, and a 32P-labelled probe for the F4 fimbriae. Plasmids possessing the enterotoxin genes ranged from 50 MDa to 78 MDa in size. The ST1 genes were located on a common 8-MDa EcoR1 restriction endonuclease fragment, while the LT1 genes were located on a 4.5-MDa EcoR1 fragment from the different plasmids. Plasmids with the F4 genes ranged from 50 MDa to 118 MDa in size, but the F4 encoding genes were located on a common 3-MDa HindIII restriction endonuclease fragment. ST1 and LT1 genes were found on the same plasmid in only one strain, LT1 and F4 genes on the same plasmids in 5 strains, while no plasmid contained genes for both ST1 and F4.
选取了十株具有K88（F4）粘附菌毛的猪源产肠毒素大肠杆菌菌株，用于研究编码肠毒素和菌毛的质粒。通过凝胶电泳按大小分离的质粒DNA，经Southern印迹转移至尼龙膜上，并用酶标记的寡核苷酸探针检测ST1和LT1肠毒素，以及用32P标记的探针检测F4菌毛。携带肠毒素基因的质粒大小在50 MDa至78 MDa之间。ST1基因位于一个常见的8-MDa EcoR1限制性内切酶片段上，而LT1基因位于来自不同质粒的4.5-MDa EcoR1片段上。携带F4基因的质粒大小在50 MDa至118 MDa之间，但F4编码基因位于一个常见的3-MDa HindIII限制性内切酶片段上。仅在一株菌株中发现ST1和LT1基因位于同一质粒上，在5株菌株中LT1和F4基因位于同一质粒上，而没有质粒同时包含ST1和F4基因。
