Functional amyloid in Pseudomonas.
Amyloids are highly abundant in many microbial biofilms and may play an important role in their architecture. Nevertheless, little is known of the amyloid proteins. We report the discovery of a novel functional amyloid expressed by a Pseudomonas strain of the P. fluorescens group. The amyloid protein was purified and the amyloid-like structure verified. Partial sequencing by MS/MS combined with full genomic sequencing of the Pseudomonas strain identified the gene coding for the major subunit of the amyloid fibril, termed fapC. FapC contains a thrice repeated motif that differs from those previously found in curli fimbrins and prion proteins. The lack of aromatic residues in the repeat shows that aromatic side chains are not needed for efficient amyloid formation. In contrast, glutamine and asparagine residues seem to play a major role in amyloid formation as these are highly conserved in curli, prion proteins and FapC. fapC is conserved in many Pseudomonas strains including the opportunistic pathogen P. aeruginosa and is situated in a conserved operon containing six genes, of which one encodes a fapC homologue. Heterologous expression of the fapA-F operon in Escherichia coli BL21(DE3) resulted in a highly aggregative phenotype, showing that the operon is involved in biofilm formation.
Dueholm
Morten S
MS
Centre for Insoluble Protein Structures, Interdisciplinary Nanoscience Center (iNANO), Department of Molecular Biology, University of Aarhus (iNANO), 8000 Aarhus C, DenmarkDepartment of Biotechnology, Chemistry, and Environmental Engineering, Aalborg University, 9000 Aalborg, DenmarkDepartments of Medical BiochemistryMedical MicrobiologyMolecular Biology, University of Aarhus (iNANO), 8000 Aarhus C, Denmark.
Petersen
Steen V
SV
Centre for Insoluble Protein Structures, Interdisciplinary Nanoscience Center (iNANO), Department of Molecular Biology, University of Aarhus (iNANO), 8000 Aarhus C, DenmarkDepartment of Biotechnology, Chemistry, and Environmental Engineering, Aalborg University, 9000 Aalborg, DenmarkDepartments of Medical BiochemistryMedical MicrobiologyMolecular Biology, University of Aarhus (iNANO), 8000 Aarhus C, Denmark.
Sønderkær
Mads
M
Centre for Insoluble Protein Structures, Interdisciplinary Nanoscience Center (iNANO), Department of Molecular Biology, University of Aarhus (iNANO), 8000 Aarhus C, DenmarkDepartment of Biotechnology, Chemistry, and Environmental Engineering, Aalborg University, 9000 Aalborg, DenmarkDepartments of Medical BiochemistryMedical MicrobiologyMolecular Biology, University of Aarhus (iNANO), 8000 Aarhus C, Denmark.
Larsen
Poul
P
Centre for Insoluble Protein Structures, Interdisciplinary Nanoscience Center (iNANO), Department of Molecular Biology, University of Aarhus (iNANO), 8000 Aarhus C, DenmarkDepartment of Biotechnology, Chemistry, and Environmental Engineering, Aalborg University, 9000 Aalborg, DenmarkDepartments of Medical BiochemistryMedical MicrobiologyMolecular Biology, University of Aarhus (iNANO), 8000 Aarhus C, Denmark.
Christiansen
Gunna
G
Centre for Insoluble Protein Structures, Interdisciplinary Nanoscience Center (iNANO), Department of Molecular Biology, University of Aarhus (iNANO), 8000 Aarhus C, DenmarkDepartment of Biotechnology, Chemistry, and Environmental Engineering, Aalborg University, 9000 Aalborg, DenmarkDepartments of Medical BiochemistryMedical MicrobiologyMolecular Biology, University of Aarhus (iNANO), 8000 Aarhus C, Denmark.
Hein
Kim L
KL
Centre for Insoluble Protein Structures, Interdisciplinary Nanoscience Center (iNANO), Department of Molecular Biology, University of Aarhus (iNANO), 8000 Aarhus C, DenmarkDepartment of Biotechnology, Chemistry, and Environmental Engineering, Aalborg University, 9000 Aalborg, DenmarkDepartments of Medical BiochemistryMedical MicrobiologyMolecular Biology, University of Aarhus (iNANO), 8000 Aarhus C, Denmark.
Enghild
Jan J
JJ
Centre for Insoluble Protein Structures, Interdisciplinary Nanoscience Center (iNANO), Department of Molecular Biology, University of Aarhus (iNANO), 8000 Aarhus C, DenmarkDepartment of Biotechnology, Chemistry, and Environmental Engineering, Aalborg University, 9000 Aalborg, DenmarkDepartments of Medical BiochemistryMedical MicrobiologyMolecular Biology, University of Aarhus (iNANO), 8000 Aarhus C, Denmark.
Nielsen
Jeppe L
JL
Centre for Insoluble Protein Structures, Interdisciplinary Nanoscience Center (iNANO), Department of Molecular Biology, University of Aarhus (iNANO), 8000 Aarhus C, DenmarkDepartment of Biotechnology, Chemistry, and Environmental Engineering, Aalborg University, 9000 Aalborg, DenmarkDepartments of Medical BiochemistryMedical MicrobiologyMolecular Biology, University of Aarhus (iNANO), 8000 Aarhus C, Denmark.
Nielsen
Kåre L
KL
Centre for Insoluble Protein Structures, Interdisciplinary Nanoscience Center (iNANO), Department of Molecular Biology, University of Aarhus (iNANO), 8000 Aarhus C, DenmarkDepartment of Biotechnology, Chemistry, and Environmental Engineering, Aalborg University, 9000 Aalborg, DenmarkDepartments of Medical BiochemistryMedical MicrobiologyMolecular Biology, University of Aarhus (iNANO), 8000 Aarhus C, Denmark.
Nielsen
Per H
PH
Centre for Insoluble Protein Structures, Interdisciplinary Nanoscience Center (iNANO), Department of Molecular Biology, University of Aarhus (iNANO), 8000 Aarhus C, DenmarkDepartment of Biotechnology, Chemistry, and Environmental Engineering, Aalborg University, 9000 Aalborg, DenmarkDepartments of Medical BiochemistryMedical MicrobiologyMolecular Biology, University of Aarhus (iNANO), 8000 Aarhus C, Denmark.
Otzen
Daniel E
DE
Centre for Insoluble Protein Structures, Interdisciplinary Nanoscience Center (iNANO), Department of Molecular Biology, University of Aarhus (iNANO), 8000 Aarhus C, DenmarkDepartment of Biotechnology, Chemistry, and Environmental Engineering, Aalborg University, 9000 Aalborg, DenmarkDepartments of Medical BiochemistryMedical MicrobiologyMolecular Biology, University of Aarhus (iNANO), 8000 Aarhus C, Denmark.
D000595:Amino Acid Sequence; D000682:Amyloid / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression; D005798:Genes, Bacterial; D023281:Genomics; D046529:Microscopy, Electron, Transmission; D008969:Molecular Sequence Data; D009876:Operon; D011551:Pseudomonas fluorescens / Q000235:genetics / Q000378:metabolism*; D053719:Tandem Mass Spectrometry
D000682:Amyloid