biostudies-literatureUnknown16Mammen CPeptidoglycan serves as the first permeability barrier of Gram-positive bacteria. Intermediates of the peptidoglycan synthesis cycle are typical targets of antimicrobial compounds, including the peptide antibiotics nisin and bacitracin. In human pathogenic bacteria, gene clusters have been identified that are upregulated to confer resistance against these compounds. One such cluster found in <i>Streptococcus agalactiae</i> encodes a Bacitracin efflux (BceAB)-type ATP binding cassette transporter, <i>Sa</i>NsrFP, and an associated two-component system, <i>Sa</i>NsrRK. <i>Sa</i>NsrFP has been shown to confer resistance against multiple antimicrobial peptides <i>in vivo</i>, with highest activity against bacitracin. Like other BceAB-type ABC-transporters, <i>Sa</i>NsrFP features a large extraFrontiers in microbiology1662803https://www.ebi.ac.uk/biostudies/studies/S-EPMC12484072biostudies-literatureThe extracellular domain of <i>Sa</i>NSrFP binds bacitracin and allows the identification of new members of the BceAB transporter family.PMC12484072Cea PReiners JGottstein JMammen CBonus MSmits SHJTantsur KGohlke HfalseThe extracellular domain of <i>Sa</i>NSrFP binds bacitracin and allows the identification of new members of the BceAB transporter family.Peptidoglycan serves as the first permeability barrier of Gram-positive bacteria. Intermediates of the peptidoglycan synthesis cycle are typical targets of antimicrobial compounds, including the peptide antibiotics nisin and bacitracin. In human pathogenic bacteria, gene clusters have been identified that are upregulated to confer resistance against these compounds. One such cluster found in <i>Streptococcus agalactiae</i> encodes a Bacitracin efflux (BceAB)-type ATP binding cassette transporter, <i>Sa</i>NsrFP, and an associated two-component system, <i>Sa</i>NsrRK. <i>Sa</i>NsrFP has been shown to confer resistance against multiple antimicrobial peptides <i>in vivo</i>, with highest activity against bacitracin. Like other BceAB-type ABC-transporters, <i>Sa</i>NsrFP features a large extra2025-01-01T00:00:00Z20252026-07-15T14:25:59.657Z2026-07-05T03:12:22.197ZS-EPMC124840724104088210.3389/fmicb.2025.1662803