title: Localization of DING proteins on PstS-containing outer-surface appendages of Pseudomonas aeruginosa.
abstract: Phosphate signaling and acquisition are critical for the bacterial response to phosphate limitation, and bacteria express multiple factors to scavenge phosphate. We previously found that multidrug-resistant strains of Pseudomonas aeruginosa from critically ill patients can form unusual outer-surface appendages harboring PstS proteins. Here, we have expanded our investigation to DING proteins that like PstS belong to the family of high-affinity phosphate-binding proteins but have strong similarity with eukaryotic DING proteins. We demonstrate the localization of DING on PstS-containing outer-surface appendages in both multidrug-resistant strain MDR25 and the PA14 strain of P. aeruginosa. However, the number of cells producing appendages and the amount of appendages on each cell in PA14 were found to be negligible, unless overexpression of either PstS or DING was achieved by transformation with constructed plasmids. We further noticed that DING expression under low phosphate conditions was significantly higher in MDR25 compared to PA14 which may explain the greater abundance of appendages in MDR25. Our finding that DING proteins are localized on extracellular appendages provides an opportunity to study the interaction of bacterial DING with host proteins by mimicking the action of host DINGs.
authors.affiliation: School of Biological Sciences, University of Auckland, Auckland, New Zealand; Department of Surgery, Pritzker School of Medicine, University of Chicago, Chicago, IL, USA.
authors.forename: Megha
authors.initials: M
authors.lastname: Shah
authors.forename: Alexander
authors.initials: A
authors.lastname: Zaborin
authors.forename: John C
authors.initials: JC
authors.lastname: Alverdy
authors.forename: Ken
authors.initials: K
authors.lastname: Scott
authors.forename: Olga
authors.initials: O
authors.lastname: Zaborina
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D022081:Cell Surface Extensions / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D028044:Phosphate-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D021381:Protein Transport; D011552:Pseudomonas Infections / Q000382:microbiology*; D011550:Pseudomonas aeruginosa / Q000235:genetics / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D028044:Phosphate-Binding Proteins
keywords: Pseudomonas aeruginosa; PstS/DING proteins; cellular appendages