Penicillinase-producing Neisseria gonorrhoeae in the Netherlands: epidemiology and genetic and molecular characterization of their plasmids

Abstract

Penicillinase-producing Neisseria gonorrhoeae strains were isolated in the Netherlands with increasing frequency during the period of 1976 to 1979. About 3% of the gonococci isolated in the first half of 1979 produced penicillinase. In contrast to the period of 1976 to 1977, most penicillinase-producing N. gonorrhoeae infections during the period of 1978 to 1979 were contracted in the Netherlands. The results of genetic and molecular studies on 80 penicillinaseproducing N. gonorrhoeae strains were similar to earlier observations of others: resistance plasmids of only two sizes, 4.5 and 3.3 megadaltons (Md), occurred in penicillinase-producing N. gonorrhoeae strains, and these encoded for the TEM-1 enzyme. The 4.5-Md plasmid could be transferred to Escherichia coli when it coexisted with a plasmid of 24 Md. The latter plasmid was present in the vast majority of the strains carrying the 4.5-Md plasmid. One strain carried a cryptic 7.5-Md plasmid in addition to the commonly found 2.5-Md plasmid. Two penicillinase-producing strains of Haemophilus parainfluenzae isolated were found to carry a 3.3-Md plasmid species which was indistinguishable from the 3.3-Md gonococcal resistance plasmids. No plasmid deoxyribonucleic acid was found in two strains of penicillinase-producing Branhamella catarrhalis, and these strains produced a penicillinase different from the TEM-1 enzyme.Penicillinase-producing Neisseria gonorrhoeae (PPNG) strains were isolated for the first time in 1976 in the United Kingdom and the United States (2, 21), and since then they have been found in many other countries (4,5,20,22,35). A significant proportion of PPNG infections encountered in several Western countries seems to have been acquired from foreign sources rather than from local contacts (1). Importation has been mainly from countries in the far east and from the west coast of Africa (1,2,5,18,20,21,27). The origin of these PPNG strains was correlated with two different types of penicillinresistance plasmids: a 4.4-megadalton (Md) plasmid originating in the far east countries and a 3.2-Md plasmid originating in west Africa (9,20,24,25).The emergence of PPNG strains at the end of 1976 (5) and their potential dissemination among the general population is of public health concem in the Netherlands. For this reason, the epidemiology of PPNG strains is studied centrally, and all PPNG strains isolated are asked to be sent to the National Institute of Public Health for confirmation of penicillinase production. Furthermore, the miniimal inhibitory concentrations of various antibiotics are determined for all PPNG strains isolated.To monitor changes at the genetic level, plasmids have been isolated and characterized from about 30% of all PPNG strains isolated in the period 1976 to the beginning of 1979. In this report we describe the results of the epidemiological data, sensitivity testing, and plasmid properties of PPNG strains. Furthermore, several isolates of penicillinase-producing strains of

Isolation and molecular characterization of beta-lactamase-producing Haemophilus parainfluenzae from the genital tract

“…All 3-lactamaseproducing strains harbored a plasmid (pLQ920) of 3.7 megadaltons (MDa), along with smaller plasmids of molecular sizes between 0.75 and 2.2 MDa. The presence of cryptic plasmids of less than 2.0 MDa was previously observed in H. parainfluenzae (2,11,17,20). Plasmid DNA purification by cesium chloride-ethidium bromide gradients (10) yielded the same patterns of bands (Fig.…”

“…Usually considered a component of the normal flora of the upper respiratory tract, H. parainfluenzae is less commonly encountered as a urogenital commensal but has nevertheless been considered to be a causative agent of urethritis in humans (3, 5,19). Rarely, P-lactamase-producing H. parainfluenzae has been isolated from genital specimens (19,20 harbored Haemophilus spp. in the anogenital area, and three strains, 11, 259, and 361, were found, by hydrolysis of the chromogenic cephalosporin nitrocefin (Oxoid Ltd., Basingstoke, England), to produce P-lactamase.…”

Properties of ß-lactamase from Neisseria gonorrhoeae

“…The isoelectric point obtained was 5.4, which suggests that this ß-lactamase isolated from N. gonorrhoeae belongs to the TEM-1 type (Van Embden et al 1980). Percival et al (1977) and Phillips (1976) found similar results in other Neisseria strains.…”

Analysis of Neisseria gonorrhoeae in Ontario, Canada, with decreased susceptibility to quinolones by pulsed-field gel electrophoresis, auxotyping, serotyping and plasmid content

“…The 10.5-MDa plasmid is of an unusual size which has not been described previously for a plasmid in N gonorrhoeae. Atypical plasmids of 7.5 and 7.8 MDa have been shown to occur in strains of N. gonorrhoeae [25,26]. Johnson et al [25] have demonstrated that these plasmids are composed of directly repeated copies of the 2.6-MDa cryptic plasmids which can be highly unstable [27].…”