PLASMID
2, 41-47(1979)
The Distribution of p-Lactamase Genes on Plasmids Found in Pseudomonas GEORGE
A. JACOBYAND
MARGARET
MATTHEW'
Massachusetts General Hospital, Boston Massachusetts 02114, and Microbiology Division, Glaxo Research Limited, Greenford, Middlesex. UB6 OHE, United Kingdom
Accepted July 22, 1978 Seven types of p-lactamases distinguished by analytic isoelectric focusing have been found on 24Pseudomonas plasmids belonging to at least eight incompatibility groups. TEM-land TEM-2-type enzymes that are determined by transposable genetic elements are distributed among five different incompatibility groups. The other p-lactamase types are found on plasmids in single incompatibility groups. /3-Lactamases unique to Pseudomonas plasmids occur on plasmids not transmissible to enterobacteria by conjugation.
Plasmids found in Pseudomonas aerugitransposable DNA sequences, are broadly nosa specify several types of /3-lactamase distributed among plasmids of various in(EC 3.5.2.6) that can be distinguished by substrate profile, the effect of inhibitors, molecular weight, and analytic isoelectric focusing (Sykes and Matthew, 1976; Matthew and Hedges, 1976; Sawadaet al., 1976; Matthew and Sykes, 1977; Hedges and Matthew, 1979; Matthew, 1978). Some have been termed Pseudomonas-specific enzymes (Hedges and Matthew, 1979) since p-lactamases of the PSE-type have not been detected in strains of enterobacteria despite intensive study (Sykes and Matthew, 1976). Others are not peculiar to Pseudomonas but occur on plasmids from various gramnegative bacteria. Among the factors involved in the distribution of p-lactamase are the host range of the plasmid involved and the ability of p-lactamase gene to undergo transposition from one plasmid to another. Many plasmids found in Pseudomonas are not transmissible to Escherichia coli and other enterobacteria by conjugation (Iyobe et al., 1974; Shahrabadi et al., 1975). p-Lactamases, notably those of the TEM-type that are specified by * Present address: New Product Services Division, Glaxo Holdings Limited, Graham Street, London Nl 8JZ, England. 41
compatibility (Inc) groups in enterobacteria (Hedges and Jacob, 1974; Heffron et al., 1975a, b; Kopecko and Cohen, 1975; Matthew and Hedges, 1976). In P. aeruginosa 11 Inc groups are currently recognized (Jacoby, 1977, unpublished observations; Korfhagen et al., 1978). We have investigated the type of /3-lactamase made by 24 Pseudomonas plasmids belonging to at least eight Inc groups to determine the role of transposons and of plasmid host range in the distribution of these enzymes. MATERIALS
AND METHODS
Bacterial strains and R plasmids. The plasmid host was P. aeruginosa PA0 strain PU21 (Jacoby, 1974). Rml6a and Rml6b, provided by B. W. Holloway, came from P. aeruginosa Ml6 isolated by H. Matsumoto. pMG18 originated in P. putida 5227-75and pMG20 came from P. aeruginosa 86-75, both provided by H. Matsumoto. pMG19 originated in P. aeruginosa Dalgleish (Newsom et al., 1970) and was transferred to PU21 by R. W. Hedges. R56 Be was supplied by Y. Michel-Briand (MichelBriand et al., 1977). The origin of the other plasmids has been summarized elsewhere (Jacoby and Shapiro, 1977). 0147-619X/79/010041-07$02.00/0 Copyright All rights
0 1979 by Academic Press. Inc. of reproduction in any form reserved.
42
JACOBY
AND MATTHEW TABLE
PROPERTIES
OF P-LACTAMASES
1
SPECIFIED
Relative
rate of hydrolysis
Pseudomonas
BY
PLASMIDS” Inhibited
/3-L% tamase
Penicillin
Ampicillin
Carbenicillin
OXacillin
Methicillin
ClOX+ cillin
Cephaloridine
Cephalothin
Cephalexin
TEM-1 TEM-2 OXAPSE- I PSE-2 PSE-3 PSE-4
100 100 100 loo 100 100 100
150 150 175 90 267 101 88
10 IO IO 97 121 235 150
0 0 520 12 317
0 0 30
2, 41-47(1979)
The Distribution of p-Lactamase Genes on Plasmids Found in Pseudomonas GEORGE
A. JACOBYAND
MARGARET
MATTHEW'
Massachusetts General Hospital, Boston Massachusetts 02114, and Microbiology Division, Glaxo Research Limited, Greenford, Middlesex. UB6 OHE, United Kingdom
Accepted July 22, 1978 Seven types of p-lactamases distinguished by analytic isoelectric focusing have been found on 24Pseudomonas plasmids belonging to at least eight incompatibility groups. TEM-land TEM-2-type enzymes that are determined by transposable genetic elements are distributed among five different incompatibility groups. The other p-lactamase types are found on plasmids in single incompatibility groups. /3-Lactamases unique to Pseudomonas plasmids occur on plasmids not transmissible to enterobacteria by conjugation.
Plasmids found in Pseudomonas aerugitransposable DNA sequences, are broadly nosa specify several types of /3-lactamase distributed among plasmids of various in(EC 3.5.2.6) that can be distinguished by substrate profile, the effect of inhibitors, molecular weight, and analytic isoelectric focusing (Sykes and Matthew, 1976; Matthew and Hedges, 1976; Sawadaet al., 1976; Matthew and Sykes, 1977; Hedges and Matthew, 1979; Matthew, 1978). Some have been termed Pseudomonas-specific enzymes (Hedges and Matthew, 1979) since p-lactamases of the PSE-type have not been detected in strains of enterobacteria despite intensive study (Sykes and Matthew, 1976). Others are not peculiar to Pseudomonas but occur on plasmids from various gramnegative bacteria. Among the factors involved in the distribution of p-lactamase are the host range of the plasmid involved and the ability of p-lactamase gene to undergo transposition from one plasmid to another. Many plasmids found in Pseudomonas are not transmissible to Escherichia coli and other enterobacteria by conjugation (Iyobe et al., 1974; Shahrabadi et al., 1975). p-Lactamases, notably those of the TEM-type that are specified by * Present address: New Product Services Division, Glaxo Holdings Limited, Graham Street, London Nl 8JZ, England. 41
compatibility (Inc) groups in enterobacteria (Hedges and Jacob, 1974; Heffron et al., 1975a, b; Kopecko and Cohen, 1975; Matthew and Hedges, 1976). In P. aeruginosa 11 Inc groups are currently recognized (Jacoby, 1977, unpublished observations; Korfhagen et al., 1978). We have investigated the type of /3-lactamase made by 24 Pseudomonas plasmids belonging to at least eight Inc groups to determine the role of transposons and of plasmid host range in the distribution of these enzymes. MATERIALS
AND METHODS
Bacterial strains and R plasmids. The plasmid host was P. aeruginosa PA0 strain PU21 (Jacoby, 1974). Rml6a and Rml6b, provided by B. W. Holloway, came from P. aeruginosa Ml6 isolated by H. Matsumoto. pMG18 originated in P. putida 5227-75and pMG20 came from P. aeruginosa 86-75, both provided by H. Matsumoto. pMG19 originated in P. aeruginosa Dalgleish (Newsom et al., 1970) and was transferred to PU21 by R. W. Hedges. R56 Be was supplied by Y. Michel-Briand (MichelBriand et al., 1977). The origin of the other plasmids has been summarized elsewhere (Jacoby and Shapiro, 1977). 0147-619X/79/010041-07$02.00/0 Copyright All rights
0 1979 by Academic Press. Inc. of reproduction in any form reserved.
42
JACOBY
AND MATTHEW TABLE
PROPERTIES
OF P-LACTAMASES
1
SPECIFIED
Relative
rate of hydrolysis
Pseudomonas
BY
PLASMIDS” Inhibited
/3-L% tamase
Penicillin
Ampicillin
Carbenicillin
OXacillin
Methicillin
ClOX+ cillin
Cephaloridine
Cephalothin
Cephalexin
TEM-1 TEM-2 OXAPSE- I PSE-2 PSE-3 PSE-4
100 100 100 loo 100 100 100
150 150 175 90 267 101 88
10 IO IO 97 121 235 150
0 0 520 12 317
0 0 30
