Peptide detection of fungal functional amyloids in infected tissue.
Many fungal cell adhesion proteins form functional amyloid patches on the surface of adhering cells. The Candida albicans Agglutinin-like sequence (Als) adhesins are exemplars for this phenomenon, and have amyloid forming sequences that are conserved between family members. The Als5p amyloid sequence mediates amyloid fibril formation and is critical for cell adhesion and biofilm formation, and is also present in the related adhesins Als1p and Als3p. We have developed a fluorescent peptide probe containing the conserved Als amyloid-forming sequence. This peptide bound specifically to yeast expressing Als5p, but not to cells lacking the adhesin. The probe bound to both yeast and hyphal forms of C. albicans. Δals1/Δals3 single and double deletion strains exhibited reduced fluorescence, indicating that probe binding required expression of these proteins. Additionally, the Als peptide specifically stained fungal cells in abscesses in autopsy sections. Counterstaining with calcofluor white showed colocalization with the amyloid peptide. In addition, fungi in autopsy sections derived from the gastrointestinal tract showed colocalization of the amyloid-specific dye thioflavin T and the fluorescent peptide. Collectively, our data demonstrate that we can exploit amyloid sequence specificity for detection of functional amyloids in situ.
Department of Biology, City University of New York Brooklyn College, Brooklyn, New York, United States of America.
Melissa C
MC
Garcia-Sherman
Department of Biology, City University of New York Brooklyn College, Brooklyn, New York, United States of America.
Nataliya
N
Lysak
Department of Biology, City University of New York Brooklyn College, Brooklyn, New York, United States of America.
Alexandra
A
Filonenko
Department of Biology, City University of New York Brooklyn College, Brooklyn, New York, United States of America.
Hazel
H
Richards
Department of Pathology, University of Arizona, Tuscon, Arizona, United States of America.
Richard E
RE
Sobonya
Division of Infectious Diseases, University of Arizona, Tuscon, Arizona, United States of America.
Stephen A
SA
Klotz
Department of Biology, City University of New York Brooklyn College, Brooklyn, New York, United States of America.
Peter N
PN
Lipke
D000595:Amino Acid Sequence; D000682:Amyloid / Q000378:metabolism*; D001344:Autopsy; D001557:Benzenesulfonates / Q000378:metabolism; D052160:Benzothiazoles; D002176:Candida albicans / Q000378:metabolism*; D002177:Candidiasis / Q000382:microbiology* / Q000473:pathology*; D005456:Fluorescent Dyes / Q000378:metabolism; D005656:Fungal Proteins / Q000737:chemistry / Q000378:metabolism; D017353:Gene Deletion; D006801:Humans; D025301:Hyphae / Q000166:cytology / Q000378:metabolism; D008969:Molecular Sequence Data; D009928:Organ Specificity; D010455:Peptides / Q000737:chemistry / Q000378:metabolism*; D011485:Protein Binding; D020836:Protein Structure, Quaternary; D012441:Saccharomyces cerevisiae / Q000166:cytology / Q000378:metabolism; D016622:Silver Staining; D013194:Staining and Labeling; D013844:Thiazoles / Q000378:metabolism
D000682:Amyloid; D001557:Benzenesulfonates; D052160:Benzothiazoles; D005456:Fluorescent Dyes; D005656:Fungal Proteins; D010455:Peptides; D013844:Thiazoles; C009462:thioflavin T; C007061:C.I. Fluorescent Brightening Agent 28