The Pseudomonas aeruginosa patatin-like protein PlpD is the archetype of a novel Type V secretion system.
We discovered a novel secreted protein by Pseudomonas aeruginosa, PlpD, as a member of the bacterial lipolytic enzyme family of patatin-like proteins (PLPs). PlpD is synthesized as a single molecule consisting of a secreted domain fused to a transporter domain. The N-terminus of PlpD includes a classical signal peptide followed by the four PLP conserved blocks that account for its lipase activity. The C-terminus consists of a POTRA (polypeptide transport-associated) motif preceding a putative 16-stranded beta-barrel similar to those of TpsB transporters of Type Vb secretion system. We showed that the C-terminus remains inserted into the outer membrane while the patatin moiety is secreted. The association between a TpsB component and a passenger protein is a unique hybrid organization that we propose to classify as Type Vd. More than 200 PlpD orthologues exist among pathogenic and environmental bacteria, which suggests that bacteria secrete numerous PLPs using this newly defined mechanism.
Salacha
Richard
R
Laboratoire d'Ingénierie des Systèmes Macromoléculaires, CNRS-Aix Marseille Université, 31 Chemin Joseph Aiguier, 13402 Marseille Cedex 20, France.
Kovacić
Filip
F
Brochier-Armanet
Céline
C
Wilhelm
Susanne
S
Tommassen
Jan
J
Filloux
Alain
A
Voulhoux
Romé
R
Bleves
Sophie
S
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry / Q000145:classification / Q000235:genetics* / Q000378:metabolism*; D002265:Carboxylic Ester Hydrolases / Q000737:chemistry / Q000145:classification / Q000235:genetics* / Q000378:metabolism*; D005089:Exocytosis / Q000502:physiology*; D006801:Humans; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000737:chemistry / Q000145:classification / Q000235:genetics* / Q000378:metabolism*; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D011550:Pseudomonas aeruginosa / Q000201:enzymology / Q000502:physiology; D016415:Sequence Alignment
D001426:Bacterial Proteins; D010940:Plant Proteins; C043222:patatin protein, Solanum tuberosum; D002265:Carboxylic Ester Hydrolases