Partial amino acid sequence of a cellulase-like component with IgE-binding properties from Stachybotrys chartarum.
BACKGROUND
The aim of this study was to characterize the amino acid sequence of a selected Stachybotrys chartarum component and to investigate human IgE reactivity against components of S. chartarum and nine other fungal species.


METHODS
Human IgE reactivity against S. chartarum and nine other fungal extracts was investigated by the immunoblotting method. For automated amino acid sequencing analyses, the S. chartarum extract was purified by ion exchange chromatography prior to in-gel alkylation and digestion with modified trypsin.


RESULTS
Human IgE reactivity was detected against eight components in the S. chartarum extract. Over 80% of the sera from the exposed subjects and less than 50% of the control sera recognized the 33-, 48- and 50-kD S. chartarum components. The human sera detected a 48- to 50-kD component from the extracts of eight fungal species. Nineteen peptide sequences were identified from the 48-kD component of S. chartarum. An analysis of the peptide sequences revealed homology with known fungal glycoside hydrolase enzymes (cellulases).


CONCLUSIONS
The data showed human IgE reactivity against several S. chartarum components, including one at 48 kD. On the other hand, the human sera recognized 48- to 50-kD components from seven other fungal species, suggesting shared antigenic components (e.g. enolase) between the fungi. Thus, to our knowledge, this is the first antigen identified from S. chartarum.
Kärkkäinen
Marja
M
Department of Environmental Sciences, University of Kuopio, Kuopio, Finland.
Raunio
Päivi
P
Rautiainen
Jaakko
J
Auriola
Seppo
S
Hinke
Kaj
K
Pasanen
Anna-Liisa
AL
D000328:Adult; D000595:Amino Acid Sequence; D002480:Cellulase / Q000737:chemistry* / Q000276:immunology / Q000302:isolation & purification; D002852:Chromatography, Ion Exchange; D005260:Female; D005656:Fungal Proteins / Q000737:chemistry / Q000276:immunology / Q000302:isolation & purification*; D006801:Humans; D015151:Immunoblotting; D007073:Immunoglobulin E / Q000097:blood / Q000276:immunology*; D007074:Immunoglobulin G / Q000097:blood; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D016415:Sequence Alignment; D013191:Stachybotrys / Q000737:chemistry / Q000276:immunology*
D005656:Fungal Proteins; D007074:Immunoglobulin G; D007073:Immunoglobulin E; D002480:Cellulase