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Volume 31, Number 11—November 2025

Research

Two Independent Acquisitions of Multidrug Resistance Gene lsaC in Streptococcus pneumoniae Serotype 20 Multilocus Sequence Type 1257

Bernard BeallComments to Author , Wuling Lin, Zhongya Li, Theresa Tran, Benjamin J. Metcalf, Bridget J. Anderson, Keipp H. Talbot, Lesley McGee, and Sopio Chochua
Author affiliation: ASRT, Inc., Smyrna, Georgia, USA (B. Beall, Z. Li); Centers for Disease Control and Prevention, Atlanta, Georgia, USA (W. Lin, T. Tran, B.J. Metcalf, L. McGee, S. Chochua); New York State Department of Health, Albany, New York, USA (B.J. Anderson); Vanderbilt University School of Medicine, Nashville, Tennessee, USA (K.H. Talbot)

Main Article

Figure 2

Complex mobile element within isolate 17 (positive for ermB, tetM, and lsaC) in study of independent acquisitions of multidrug resistance gene lsaC in serotype 20/ST1257 Streptococcus pneumoniae isolates, United States. A) Predicted mobile element genes and functions. B) The insertion site is depicted between rplL and atpB in pansusceptible genome serotype 20/ST1257 with rplL 3′ 15 bp target site highlighted in yellow. The alignment between corresponding genomic regions of isolate 17 and S. intermedius strain 270 is shown with 15 bp repeat of rpllL 3′ end indicated upstream of genomic atpB gene in isolate 16 and upstream of unidentified open frames in S. intermedius 270. Although the S. intermedius rplL gene had an identical 15-bp terminus, it only shares 90% sequence identity with the pneumococcal rplL gene. The original EasyFig (20) output was modified to depict the interspecies homology between the 2 rplL homologs. Homology legend indicates range of 77%–100% sequence identity, depicting ≈90% sequence identity between the 2 different rplL alleles and >96% sequence identity between the 2 insertion elements. ST, sequence type.

Figure 2. Complex mobile element within isolate 17 (positive for ermB, tetM, and lsaC) in study of independent acquisitions of multidrug resistance gene lsaC in serotype 20/ST1257 Streptococcus pneumoniae isolates, United States. A) Predicted mobile element genes and functions. B) The insertion site is depicted between rplL and atpB in pansusceptible genome serotype 20/ST1257 with rplL 3′ 15 bp target site highlighted in yellow. The alignment between corresponding genomic regions of isolate 17 and S. intermedius strain 270 is shown with 15 bp repeat of rpllL 3′ end indicated upstream of genomic atpB gene in isolate 16 and upstream of unidentified open frames in S. intermedius 270. Although the S. intermedius rplL gene had an identical 15-bp terminus, it only shares 90% sequence identity with the pneumococcal rplL gene. The original EasyFig (20) output was modified to depict the interspecies homology between the 2 rplL homologs. Homology legend indicates range of 77%–100% sequence identity, depicting ≈90% sequence identity between the 2 different rplL alleles and >96% sequence identity between the 2 insertion elements. ST, sequence type.

Main Article

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