Restriction enzyme fingerprinting of enterobacterial plasmids: a simple strategy with wide application

Abstract

SUMMARYRestriction enzyme fingerprints were generated from purified plasmid DNA from 324 clinical isolates that belonged to 7 enterobacterial genera and 88 single plasmids in Escherichia coli K 12 according to the following strategy.Purified plasmid DNA was digested with PstI. The number of fragments detected in a 0-8 agarose gel was used to determine which 2 of 6 restriction enzymes including PstI was most likely to provide a fingerprint comprising sufficient fragments to ensure specificity but sufficiently few to allow easy visual assessment and minimize coincidental matching. When Pst I produced > 20 fragments, Eco RI and Hind III were used; when PstI generated < 6 fragments Bsp 1286 and AvaII were used and SmaI was employed when between 6 and 20 fragments were obtained from PstI digests. Using a minimum of 12 fragments from a combination of 2 enzymes as the criterion for characterizing a strain/plasmid, satisfactory 2-enzyme fingerprints were obtained from 87 % of the strains and plasmids studied using Pst I and no more than two additional enzymes per strain. Of the remaining 54 strains, 51 harboured only small plasmids (< 10 kb) and 3 produced satisfactory fingerprints when digested with a fourth enzyme.

Restriction endonuclease characterization of resistant plasmids in Enterobacteriaceae isolated from children in the Sudan

“…The findings from our study confirm those of others (12,13,19) However, other studies have shown that both of these transposons may occur in isolates from the tropics and may contribute to the widespread dissemination of resistant genes between species (8,20). The number of fragments generated by single enzymes is not sufficiently discriminatory to be useful in plasmid classification, but combining the results from two different digests does provide a basis for classification.…”

“…Combined enzyme patterns The combination of digest results from more than one enzyme has been shown to be a possible basis for plasmid grouping (12). Table 3 shows the grouping of the plasmids based on a combination of the fragment numbers using Pst I and EcoR I.…”

“…Measures to reduce the spread of resistance, and to predict likely resistance problems in future outbreaks, require effective methods for the surveillance,9nd the classification of resistance plasmids (9). While incompatibility grouping has been the basis of plasmid classification (10), and has been shown to be of value in comparing plasmids from outbreaks in different geographical locations (11), recent studies have shown the value of restriction endonuclease characterization in the study of transferableresistance plasmids (12,13). As part of a study of antibiotic resistance in enteric flora isolated from children in Khartoum, Sudan, we have investigated the use of restriction endonuclease digestion to characterize resistant transconjugant plasmids.…”

“…As part of a study of antibiotic resistance in enteric flora isolated from children in Khartoum, Sudan, we have investigated the use of restriction endonuclease digestion to characterize resistant transconjugant plasmids. Resistance pattern pKc [1][2][3][4][5][6][7][8] Ap Su Tm Sm pKc9,10 TcC pKcl11 Ap Tm pKc [12][13][14][15] Tm pKc 16 Ap Tc PKc 17 Ap Su Tm Sm C pKc 18,19 ApTcSuTmSm pKc 20 Ap Su Tm pKc 21 Ap Tc Su Tm Sm C pKc 22 Ap Tc C pKc 23,24 Ap PATIENTS AND METHODS…”

Interrelationships between strains ofSalmonella enteritidis

“…Plasmid fingerprinting Fingerprinting of plasmids using a variety of restriction endonucleases is a technique which may extend the results of plasmid profile typing [15]. However, fingerprinting of plasmids in the type strains of the S. enteritidis phage types, using the restriction endonucleases Hind III and Pst I has demonstrated a remarkable degree of homogeneity amongst the plasmids of 38 MDa, identified in 18 of the 27 phage type strains studied [16].…”