TY - JOUR
T1 - Advanced resistance studies identify two discrete mechanisms in Staphylococcus aureus to overcome antibacterial compounds that target biotin protein ligase
AU - Hayes, Andrew J.
AU - Satiaputra, Jiulia
AU - Sternicki, Louise M.
AU - Paparella, Ashleigh S.
AU - Feng, Zikai
AU - Lee, Kwang J.
AU - Blanco-Rodriguez, Beatriz
AU - Tieu, William
AU - Eijkelkamp, Bart A.
AU - Shearwin, Keith E.
AU - Pukala, Tara L.
AU - Abell, Andrew D.
AU - Booker, Grant W.
AU - Polyak, Steven W.
PY - 2020/4
Y1 - 2020/4
N2 - Biotin protein ligase (BPL) inhibitors are a novel class of antibacterial that target clinically important methicillin-resistant Staphylococcus aureus (S. aureus). In S. aureus, BPL is a bifunctional protein responsible for enzymatic biotinylation of two biotin-dependent enzymes, as well as serving as a transcriptional repressor that controls biotin synthesis and import. In this report, we investigate the mechanisms of action and resistance for a potent anti-BPL, an antibacterial compound, biotinylacylsulfamide adenosine (BASA). We show that BASA acts by both inhibiting the enzymatic activity of BPL in vitro, as well as functioning as a transcription co-repressor. A low spontaneous resistance rate was measured for the compound (<10-9) and whole-genome sequencing of strains evolved during serial passaging in the presence of BASA identified two discrete resistance mechanisms. In the first, deletion of the biotin-dependent enzyme pyruvate carboxylase is proposed to prioritize the utilization of bioavailable biotin for the essential enzyme acetyl-CoA carboxylase. In the second, a D200E missense mutation in BPL reduced DNA binding in vitro and transcriptional repression in vivo. We propose that this second resistance mechanism promotes bioavailability of biotin by derepressing its synthesis and import, such that free biotin may outcompete the inhibitor for binding BPL. This study provides new insights into the molecular mechanisms governing antibacterial activity and resistance of BPL inhibitors in S. aureus.
AB - Biotin protein ligase (BPL) inhibitors are a novel class of antibacterial that target clinically important methicillin-resistant Staphylococcus aureus (S. aureus). In S. aureus, BPL is a bifunctional protein responsible for enzymatic biotinylation of two biotin-dependent enzymes, as well as serving as a transcriptional repressor that controls biotin synthesis and import. In this report, we investigate the mechanisms of action and resistance for a potent anti-BPL, an antibacterial compound, biotinylacylsulfamide adenosine (BASA). We show that BASA acts by both inhibiting the enzymatic activity of BPL in vitro, as well as functioning as a transcription co-repressor. A low spontaneous resistance rate was measured for the compound (<10-9) and whole-genome sequencing of strains evolved during serial passaging in the presence of BASA identified two discrete resistance mechanisms. In the first, deletion of the biotin-dependent enzyme pyruvate carboxylase is proposed to prioritize the utilization of bioavailable biotin for the essential enzyme acetyl-CoA carboxylase. In the second, a D200E missense mutation in BPL reduced DNA binding in vitro and transcriptional repression in vivo. We propose that this second resistance mechanism promotes bioavailability of biotin by derepressing its synthesis and import, such that free biotin may outcompete the inhibitor for binding BPL. This study provides new insights into the molecular mechanisms governing antibacterial activity and resistance of BPL inhibitors in S. aureus.
KW - Advanced resistance studies
KW - Antimicrobial resistance
KW - Biotin
KW - Biotin protein ligase
KW - Bira
KW - Gram-positive bacteria
KW - Novel antibacterials
KW - Staphylococcus aureus
UR - http://www.scopus.com/inward/record.url?scp=85083767559&partnerID=8YFLogxK
U2 - 10.3390/antibiotics9040165
DO - 10.3390/antibiotics9040165
M3 - Article
C2 - 32268615
AN - SCOPUS:85083767559
SN - 2079-6382
VL - 9
JO - Antibiotics
JF - Antibiotics
IS - 4
M1 - 165
ER -