DNA sequence and regulation of ermD, a macrolide-lincosamide-streptogramin B resistance element from Bacillus licheniformis

Abstract

The DNA sequence of ermD , a macrolide-lincosamide-streptogramin B (MLS) resistance determinant cloned from the chromosome of Bacillus licheniformis, has been determined. ermD encodes an erythromycin inducible protein of molecular weight 32,796. S1 nuclease mapping of the ermD promoter has revealed the presence of an approximately 354 base leader sequence on the ermD transcript. This leader contains a short open reading frame sufficient to encode a 14 amino acid peptide, which is preceded by a potential ribosomal binding site. The leader sequence has the potential to fold into several base paired structures, in some of which the ribosomal binding site for the ermD product would be sequestered. Deletion analysis demonstrated that the leader contains regulatory sequences. Removal of the ermD promoter and fusion to an upstream promoter did not interfere with induction, strongly suggestion that ermD regulation is posttranscriptional. Based on these features it appears likely that ermD is regulated by a translational attenuation mechanism, analogous to that suggested for ermC , a resistance element from Staphylococcus aureus ( Gryczan et al. 1980; Horinouchi and Weisblum 1980). Comparison of the ermD sequence and that of its product to two other sequenced MLS determinants reveals substantial phylogenetic relatedness, although the three genes are not homologous by the criterion of Southern blot hybridization.

DNA homology between Saccharopolyspora strains and other erythromycin-producing actinomycetes

“…and ermA. Although other MLS-resistance genes isolated from bacilli, streptococci and staphylococci do not possess comparable DNA sequence similarities (Gryczan et al, 1984), many of these resistance genes (including ermE and ermA) exhibit substantial similarity at the amino acid level, an observation consistent with the proposal that antibiotic resistance genes may have evolved in antibiotic-producing actinomycetes and were subsequently transferred to other micro-organisms (Benveniste & Davies, 1973).…”

A Macrolide-Lincosamide-Streptogramin B Resistance Determinant from Bacillus Anthracis 590: Cloning and Expression of ermJ

“…Another Shine-Dalgarno region (SD-2) was located upstream of this large ORF. When the nucleotide sequence of ermJ was compared with the sequences of other erm genes, it showed similarity to those of ermK and ermD, the MLS resistance elements cloned from B. Zicheniformis (Gryczan et al, 1984;Kwak et al, 1991). There are 28 nucleotide and 9 amino acid differences between ermJ and ermK in a comparison of 1324 nucleotides and 287 amino acids (Table 2).…”

“…Activation involves altering the secondary structure of mRNA, and is brought about by stalling an Em-ribosome complex on a leader region encoding a short polypeptide. The existence of translational attenuation has also been suggested in ermA (Murphy, 1985), ermD (Gryczan et al, 1984), ermG (Monod et al, 1987), ermSF (Kamimiya & Weisblum, 1988) and ermAM (Horinouchi et al, 1983). In contrast to the translational attenuation associated with most MLS resistance genes, transcriptional regulation has been found in ermK, the MLS-resistant element isolated from B. licheniformis.…”

Transformation of Arthrobacter and studies on the transcription of the Arthrobacter ermA gene in Streptomyces lividans and Escherichia coli

“…Relationship between the expression of erythromycin resistance genes Erythromycin resistance genes examined are either expressed constitutively or induced by erythromycin by a translational attenuation mehanism . Genes that are inducible by erythromycin are characterized by a leader sequence preceding the coding sequence (Gryczan et al, 1980(Gryczan et al, , 1984Horinouchi & Weisblum, 1980;Horinouchi et al, 1983;Murphy, 1985) which is absent from constitutively expressed genes (Lampson & Parisi, 1986;Monod et al, 1986). Examination of the nucleotide sequence and SI mapping data of the erythromycin resistance genes ermA and ermE from two organisms that produce the antibiotic, Arthrobacter and S. erythreus (Roberts et al, 1985;Bibb et al, 1985a;Uchiyama & Weisblum, 1985), show that a leader sequence is not present.…”