Ms. Zao et al., PLASMID PROFILE OF YERSINIA-PESTIS STRAINS IN DIFFERENT NATURAL FOCI OF PLAGUE IN THE CHINESE-PEOPLES-REPUBLIC, Zurnal mikrobiologii, epidemiologii i immunobiologii, (2), 1993, pp. 27-31
A total of 159 Y. pestis strains isolated in different geographical re
gions of China have been studied. Y. pestis isolated in the majority o
f natural foci of plague in China carry plasmids with molecular weight
s of 6, 13, 15 and 63 MD. One isolated strain has been found to carry
plasmid with a molecular weight of 36 MD. Only a few strains have no p
lasmids with molecular weights of 6 and 45 MD. In certain geographical
zones strains carrying large plasmids of 52 and 92 MD have been detec
ted.