1)沖縄県家畜衛生試験場(〒900-0024 那覇市古波蔵112) 2)沖縄県中央家畜保健衛生所(〒901-1202 沖縄県島尻郡大里村字大里2505) |
(1998年12月22日受付・1999年11月11日受理)
1994〜1997年に沖縄県内で分離された子牛由来Vero毒素産生性大腸菌(verotoxin-producing Escherichia coli:VTEC)35株について,血清型,毒素産生性,病原遺伝子,薬剤感受性およびプラスミドプロファイルによる解析を行った.血清型はO群型ではO111が8株,O26が4株,O157が2株,O113,O119,O124が各1株,Rough型6株,型別不能12株であった.逆受身ラテックス凝集反応法とPCR法によるVero毒素型別では,VT1産生菌が26株,VT2産生菌が8株,VT1とVT2産生菌が1株であった.また16株が病原遺伝子eaeAを,17株がhlyAを保有していたが,bfpおよびaggRは全例陰性であった.薬剤感受性では7剤多剤耐性株をはじめ,23株(65.7%)が供試10薬剤のいずれかに耐性であった.分離株のすべては1〜6種類のプラスミドを保有し,O157:H7株では90kbの病原性プラスミドおよび分子量の小さいプラスミドが確認された.
--------------------日獣会誌 53,279〜284(2000)
Biological Properties, Drug Susceptibility, and Plasmid Analysis of Verotoxin-producing Escherichia coli (VTEC) Isolated from CalvesMasanao MATAYOSHI*, Mamoru OSHIRO, Makoto AFUSO and Tamotsu KOKUBA
SUMMARY Thirty-five strains of verotoxin-producing Escherichia coli (VTEC) isolated mainly
from diarrheal calves in Okinawa Prefecture between 1994 and 1997 were investigated for biological properties.
The VTEC belonged to 6 serogroups―O111 (8 strains), O26 (4 strains), O157 (2 strains), O113 (1 strain),
O119 (1 strain), O124 (1 strain), rough (6 strains), and 12 untypable strains. Verotoxin typing by means
of gene analysis using the polymerase chain reaction (PCR) showed that 26 strains (74.3%) carried VT1
genes and 8 (22.9%) carried VT2 genes. The eaeA gene was detected in 16 strains (45.7%) and the hlyA gene
in 17 strains (48.6%), though negative results were obtained for both the bfpA gene and the aggR gene.
Twenty-three strains (65.7%) were resistant to at least 1 of the 10 tested antibiotics, and 1 strain
demonstrated multiple resistance to 7 antibiotics. All isolates possess from 1 to 6 plasmids. The O157
: H7 strain possessed the 90-kb virulence plasmid and several smaller plasmids.
--------------------J. Jpn. Vet. Med. Assoc., 53, 279〜284 (2000) |