Macrolide Esterase-producing Escherichia coli Clinically Isolated in Japan.

Abstract

Current Japanese clinical practice involves the usage of large amounts of new macrolides such as clarithromycin and roxithromycin for the treatment of diffuse panbronchiolitis, Helicobacter pylori and Mycobacterium avium complex infections. In this study, the phenotypes, genotypes, and macrolide resistance mechanisms of macrolide-inactivating Escherichia coll recovered in Japan from 1996 to 1997, were investigated.The isolation rate of erythromycin A highly-resistant E. coli (MIC > 1600 /xg/ml) in Japan slightly increased from 0.5% in 1986 to 1.2% in 1997. In six macrolide-resistant strains, recovered from the strains collected for this study during 1996 to 1997, the inactivation of macrolide could be detected with or without added ATPin the assay system. The appearance of erythromycin A-inactivating enzyme independent of ATPwas novel from Japanese isolates, and the ]H NMRspectra of oleandomycin hydrolyzed by the three ATP-independent isolates were examined. It was clearly shown that the lactone ring at the position of C-13 was cleaved as 13-H signal in aglycon of oleandomycin upper shifted. These results suggested the first detection of macrolide-lactone ring-hydrolase from clinical isolates in Japan. These results suggested the first detection of an ATP-independent macrolide-hydrolyzing enzyme from Japanese clinical isolates. Substrate specificity of the macrolide-hydrolyzing enzyme was determined with twelve macrolides including the newer membersof this group and it was found that not only erythromycin A but also the new macrolides, such as clarithromycin, roxithromycin, and azithromycin were inactivated. The NMRdata, broad spectrum of activity, and independence of co-enzymesupported our namingof the enzymeas a macrolide esterase. PCRmethodology was employed to detect an ereB-like gene from the 3 isolates producing macrolide esterase, and one of these was subsequently shown to contain both ereB-like and ermB-Wksgenes. It was also clearly shown that the other three isolates, which inactivated macrolide in the presence of ATP, had an mphA-liko gene.

The mef (A) Gene Predominates among Seven Macrolide Resistance Genes Identified in Gram-Negative Strains Representing 13 Genera, Isolated from Healthy Portuguese Children

“…Unfortunately, there is little previously published data from other countries available for comparison of data, because most studies have focused on macrolide resistance in pathogenic bacteria from clinical settings and/or diseased hosts (1,3,4,6,7,9,11,12,(14)(15)(16)(17)(18)22). However, we can compare these results with those of an earlier study by Luna et al (8) on 615 randomly selected, commensal, gram-positive isolates from the same group of Lisbon children as the current study over the same time period.…”

Detection and Characterization of a Macrolide 2′-Phosphotransferase from a Pseudomonas aeruginosa Clinical Isolate

“…In the United Kingdom, azithromycin has been used for cystic fibrosis patients infected with P. aeruginosa (3). Recently, highly macrolide-resistant strains, producing erythromycin esterase (1,6) or macrolide 2Ј-phosphotransferase [MPH(2Ј)] (5, 7, 9), have been recovered with increasing frequency in clinical isolates of members of the family Enterobacteriaceae and also staphylococci (8). No reports, however, have yet been published regarding the presence of a macrolide-inactivating enzyme in P. aeruginosa.…”

“…Transfer of the macrolide resistance phenotype from these P. aeruginosa isolates could not be demonstrated, as the transfer frequencies to the recipient strain P. aeruginosa PAO2142Rp were less than 10 Ϫ8 . Enzymatic inactivation of macrolides using crude extracts with or without a cofactor (40 mM ATP, 40 mM GTP, 2 mM acetyl coenzyme A, 40 mM NAD, 40 mM NADP, 40 mM UDPG, or 80 mM GSH) was determined by measuring residual macrolide activity (6). It was demonstrated that the inactivation of oleandomycin using crude extracts from the two isolates was dependent on only ATP or GTP (Table 1).…”

Purification and characterization of an erythromycin esterase from an erythromycin-resistant Pseudomonas sp.

“…Rachek et al [10] described the expression of the E. coli ereB gene in a parasitic Rickettsia prowazekii. The isolation rate of macrolide-inactivating E. coli (MIC v 1600 Wg ml 31 ) tends to increase in Japanese clinical samples [11].…”