The Pseudomonas aeruginosa PA14 ABC Transporter NppA1A2BCD Is Required for Uptake of Peptidyl Nucleoside Antibiotics.
Analysis of the genome sequence of Pseudomonas aeruginosa PA14 revealed the presence of an operon encoding an ABC-type transporter (NppA1A2BCD) showing homology to the Yej transporter of Escherichia coli. The Yej transporter is involved in the uptake of the peptide-nucleotide antibiotic microcin C, a translation inhibitor that targets the enzyme aspartyl-tRNA synthetase. Furthermore, it was recently shown that the Opp transporter from P. aeruginosa PAO1, which is identical to Npp, is required for uptake of the uridyl peptide antibiotic pacidamycin, which targets the enzyme translocase I (MraY), which is involved in peptidoglycan synthesis. We used several approaches to further explore the substrate specificity of the Npp transporter. Assays of growth in defined minimal medium containing peptides of various lengths and amino acid compositions as sole nitrogen sources, as well as Biolog Phenotype MicroArrays, showed that the Npp transporter is not required for di-, tri-, and oligopeptide uptake. Overexpression of the npp operon increased susceptibility not just to pacidamycin but also to nickel chloride and the peptidyl nucleoside antibiotic blasticidin S. Furthermore, heterologous expression of the npp operon in a yej-deficient mutant of E. coli resulted in increased susceptibility to albomycin, a naturally occurring sideromycin with a peptidyl nucleoside antibiotic. Additionally, heterologous expression showed that microcin C is recognized by the P. aeruginosa Npp system. Overall, these results suggest that the NppA1A2BCD transporter is involved in the uptake of peptidyl nucleoside antibiotics by P. aeruginosa PA14.


OBJECTIVE
One of the world's most serious health problems is the rise of antibiotic-resistant bacteria. There is a desperate need to find novel antibiotic therapeutics that either act on new biological targets or are able to bypass known resistance mechanisms. Bacterial ABC transporters play an important role in nutrient uptake from the environment. These uptake systems could also be exploited by a Trojan horse strategy to facilitate the transport of antibiotics into bacterial cells. Several natural antibiotics mimic substrates of peptide uptake routes. In this study, we analyzed an ABC transporter involved in the uptake of nucleoside peptidyl antibiotics. Our data might help to design drug conjugates that may hijack this uptake system to gain access to cells.
Jacobs University Bremen, Department of Life Sciences and Chemistry, Bremen, Germany.
Daniel
http://orcid.org/0000-0001-5750-7505
D
Pletzer
Jacobs University Bremen, Department of Life Sciences and Chemistry, Bremen, Germany.
Yvonne
Y
Braun
Russian Academy of Sciences, Institute of Gene Biology and Institute of Molecular Genetics, Moscow, Russia.
Svetlana
S
Dubiley
Sanofi-Aventis R&D, Infectious Diseases Therapeutic Unit, Toulouse, France.
Corinne
C
Lafon
University Hospital Geneva, Department of Microbiology and Molecular Medicine and Service of Infectious Diseases, Geneva, Switzerland.
Thilo
T
Köhler
Basilea Pharmaceutica International Ltd., Basel, Switzerland.
Malcolm G P
MGP
Page
Sanofi-Aventis R&D, Infectious Diseases Therapeutic Unit, Toulouse, France.
Michael
M
Mourez
Russian Academy of Sciences, Institute of Gene Biology and Institute of Molecular Genetics, Moscow, Russia.|Waksman Institute for Microbiology, Rutgers, The State University of New Jersey, Piscataway, New Jersey, USA.
Konstantin
K
Severinov
Jacobs University Bremen, Department of Life Sciences and Chemistry, Bremen, Germany h.weingart@jacobs-university.de.
Helge
H
Weingart
D018528:ATP-Binding Cassette Transporters / Q000235:genetics / Q000378:metabolism*; D000900:Anti-Bacterial Agents / Q000378:metabolism*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D001430:Bacteriocins / Q000378:metabolism; D001692:Biological Transport; D005291:Ferrichrome / Q000031:analogs & derivatives / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial / Q000502:physiology; D026901:Membrane Transport Proteins / Q000378:metabolism; D009705:Nucleosides / Q000378:metabolism; D011550:Pseudomonas aeruginosa / Q000235:genetics / Q000378:metabolism*
D018528:ATP-Binding Cassette Transporters; D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D001430:Bacteriocins; D026901:Membrane Transport Proteins; D009705:Nucleosides; C020411:microcin; D005291:Ferrichrome; C015657:albomycin; C004500:blasticidin S