Disease relevance of strB

• All ampicillin- and streptomycin-resistant E. coli O26 carried ampC and strA-strB gene sequences, respectively [1].
• Three streptomycin (SM) production genes from Streptomyces griseus clustered around aphD, the major resistance gene, have been sequenced: strB, coding for an aminocyclitol amidinotransferase, ORF5 (strR), a putative regulatory gene, and ORF1 (strD), possibly coding for a hexose nucleotidylating enzyme [2].
• Deletions in either of the genes in the strA-strB gene pair of Erwinia amylovora plasmid pEa34 resulted in a dramatic decrease in streptomycin resistance (SmR), but SmR was restored to high levels by complementation [3].
• A PCR was developed and used for detection of the strA-strB gene pair encoding streptomycin resistance in gram-negative bacteria [4].
• Several strains, which belonged to different species of Neisseria, were resistant to beta-lactams, streptomycin, sulfamethoxazole, and trimethoprim, harbored a 6.0-megadalton plasmid with identical HinfI restriction patterns, and produced beta-lactamase and streptomycin phosphotransferase [5].

High impact information on strB

• Other genes conferring resistance to aminoglycosides (aacC2, strA, and strB), chloramphenicol (catA2), sulfonamides (sul2), tetracycline (tetD), and trimethoprim (dfrA14) were also detected in pK245 [6].
• We conclude that an R plasmid coding for beta-lactamase, streptomycin phosphotransferase, and a sulfonamide-resistant dihydropteroate synthetase is common to these strains [5].
• Negative associations were found between resistance genes encoding resistance to the same antimicrobial agent: tet(A)/tet(B), sul1/sul2 and strA-strB/aadA1 [7].
• PCR was carried out for detection of the streptomycin resistance genes strA-strB and the integron-associated aadA gene cassettes [8].
• A gene (hur) from Streptomyces aureofaciens, conferring resistance to hydroxyurea, is related to genes encoding streptomycin phosphotransferase [9].

Chemical compound and disease context of strB

• Expression and identification of the strA-strB gene pair from streptomycin-resistant Erwinia amylovora [3].
• Characterisation of the hydroxystreptomycin phosphotransferase gene (sph) of Streptomyces glaucescens: nucleotide sequence and promoter analysis [10].

Biological context of strB

• Other plasmids carrying floR and aadB also carried tet(A), sul2, strA/strB, bla(CMY-2) and occasionally aac(3)IV [11].
• An str gene cluster containing at least four genes (strR, strA, strB, and strC) involved in streptomycin biosynthesis or streptomycin resistance or both was self-cloned in Streptomyces griseus by using plasmid pOA154 [12].
• The promoter region of the sph gene appears to be complex since tandemly arranged promoters (orfIp1, orfIp2) initiating transcription of a likely coding region (ORFI) in the opposite direction overlap sph promoter sequences [10].
• Evidence for an ATG as translation start codon for sph was derived from a comparison with the amino-terminal amino acid sequence of an aminoglycoside phosphotransferase (aphD gene product) of S. griseus, exhibiting a high degree of amino acid homology to the deduced amino acid sequence of the S. glaucescens sph gene product [10].
• It contains a conditional origin of replication (oriR6K), the strAB genes encoding the streptomycin phosphotransferase (SmR), an origin of transfer (mobRK2), the sacB gene mediating sucrose sensitivity, and multiple cloning sites [13].

Associations of strB with chemical compounds

• Moreover, a truncated copy of Tn5393 with complete streptomycin resistance genes strA and strB was found upstream of the floR gene of pMBSF1 [14].
• The broad host range cosmid pLZO3 carries a gentamicin acetyltransferase gene as bacterial selective marker and tandem, chimeric neomycin and streptomycin phosphotransferase genes as plant selective markers [15].

References