[Corynebacterium diphtheriae nontoxigenic strain carrying the gene of diphtheria toxin].

Autor: Mel'nikov VG; Gabrichevsky Research Institute of Epidemiology and Microbiology, Moscow, Russia., Kombarova SIu, Borisova OIu, Volozhantsev NV, Verevkin VV, Volkovoĭ KI, Mazurova IK
Jazyk: ruština
Zdroj: Zhurnal mikrobiologii, epidemiologii i immunobiologii [Zh Mikrobiol Epidemiol Immunobiol] 2004 Jan-Feb (1), pp. 3-7.
Abstrakt: Among 828 C. diphtheriae nontoxigenic cultures isolated in different region of Russia in 1994-2002, 114 cultures (13.8%) had the gene of diphtheria toxin (gene tox) and were thus called nontoxigenic tox-carrying (NTTC) strains. All NTTC strains were found to belong to biovar mitis and formed neither normal, nor "defective" diphtheria toxin. The most of NTTC strains (94%) belonged to ribotype "Moskva", not occurring among C. diphtheriae toxigenic strains. The incapacity of NNTC strains of forming diphtheria toxin was caused by mutation: the deletion of one nucleotide which led to the shift of the open reading frame and to the formation of the stop codon. The results of these studies are indicative of the fact that a sufficiently homogeneous and isolated group of C. diphtheriae nontoxigenic strains is spread in Russia. These strains carry the nonexpressing gene of diphtheria toxin and are of no epidemic importance in diphtheria infection.
Databáze: MEDLINE