A Novel Putrescine Exporter SapBCDF of Escherichia coli.
Recent research has suggested that polyamines (putrescine, spermidine, and spermine) in the intestinal tract impact the health of animals either negatively or positively. The concentration of polyamines in the intestinal tract results from the balance of uptake and export of the intestinal bacteria. However, the mechanism of polyamine export from bacterial cells to the intestinal lumen is still unclear. In Escherichia coli, PotE was previously identified as a transporter responsible for putrescine excretion in an acidic growth environment. We observed putrescine concentration in the culture supernatant was increased from 0 to 50 μm during growth of E. coli under neutral conditions. Screening for the unidentified putrescine exporter was performed using a gene knock-out collection of E. coli, and deletion of sapBCDF significantly decreased putrescine levels in the culture supernatant. Complementation of the deletion mutant with the sapBCDF genes restored putrescine levels in the culture supernatant. Additionally, the ΔsapBCDF strain did not facilitate uptake of putrescine from the culture supernatant. Quantification of stable isotope-labeled putrescine derived from stable isotope-labeled arginine supplemented in the medium revealed that SapBCDF exported putrescine from E. coli cells to the culture supernatant. It was previously reported that SapABCDF of Salmonella enterica sv. typhimurium and Haemophilus influenzae conferred resistance toantimicrobial peptides; however, the E. coli ΔsapBCDF strain did not affect resistance to antimicrobial peptide LL-37. These results strongly suggest that the natural function of the SapBCDF proteins is the export of putrescine.
From the Division of Applied Life Science, Graduate School of Bioresources and Environmental Sciences, Ishikawa Prefectural University, Nonoichi, Ishikawa 921-8836.
Yuta
Y
Sugiyama
the Dairy Science and Technology Institute, Kyodo Milk Industry Co. Ltd., Tokyo 190-0182.
Atsuo
A
Nakamura
the Dairy Science and Technology Institute, Kyodo Milk Industry Co. Ltd., Tokyo 190-0182.
Mitsuharu
M
Matsumoto
the Division of Applied Biology, Kyoto Institute of Technology, Kyoto 606-8585.
Ayaka
A
Kanbe
From the Division of Applied Life Science, Graduate School of Bioresources and Environmental Sciences, Ishikawa Prefectural University, Nonoichi, Ishikawa 921-8836.
Mikiyasu
M
Sakanaka
the Division of Biopharmaceutical Sciences, Graduate School of Pharmaceutical Sciences, Chiba University, Chiba 260-8675.
Kyohei
K
Higashi
the Amine Pharma Research Institute, Innovation Plaza at Chiba University, Chiba 260-0856, and.
Kazuei
K
Igarashi
From the Division of Applied Life Science, Graduate School of Bioresources and Environmental Sciences, Ishikawa Prefectural University, Nonoichi, Ishikawa 921-8836.|the Division of Integrated Life Science, Graduate School of Biostudies, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan.
Takane
T
Katayama
the Division of Applied Biology, Kyoto Institute of Technology, Kyoto 606-8585.
Hideyuki
H
Suzuki
From the Division of Applied Life Science, Graduate School of Bioresources and Environmental Sciences, Ishikawa Prefectural University, Nonoichi, Ishikawa 921-8836, kuri711@ishikawa-pu.ac.jp.
Shin
S
Kurihara
D018528:ATP-Binding Cassette Transporters / Q000235:genetics / Q000378:metabolism*; D023181:Antimicrobial Cationic Peptides / Q000494:pharmacology; D017920:Antiporters / Q000235:genetics / Q000378:metabolism*; D001693:Biological Transport, Active / Q000187:drug effects / Q000502:physiology; D024881:Drug Resistance, Bacterial / Q000187:drug effects / Q000502:physiology; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism*; D011700:Putrescine / Q000378:metabolism*; D054804:Cathelicidins
D018528:ATP-Binding Cassette Transporters; D023181:Antimicrobial Cationic Peptides; D017920:Antiporters; D029968:Escherichia coli Proteins; C071519:PotE protein, E coli; C443121:SapD protein, E coli; D011700:Putrescine; D054804:Cathelicidins
Escherichia coli (E. coli); antimicrobial peptide; bacterial metabolism; gut microbe; polyamine; transporter