TY - JOUR
T1 - Prediction of flocculation ability of brewing yeast inoculates by flow cytometry, proteome analysis, and mRNA profiling
AU - Heine, Franziska
AU - Stahl, Frank
AU - Sträuber, Heike
AU - Wiacek, Claudia
AU - Benndorf, Dirk
AU - Repenning, Cornelia
AU - Schmidt, Frank
AU - Scheper, Thomas
AU - von Bergen, Martin
AU - Harms, Hauke
AU - Müller, Susann
AU - von Bergen, Martin
N1 - Copyright 2008 International Society for Advancement of Cytometry
PY - 2009/2
Y1 - 2009/2
N2 - The ability of brewing yeast to flocculate is an important feature for brewing of qualitatively good beer. Flocculation involves two main cell wall structures, which are the flocculation proteins (flocculins) and mannans, to which these flocculins bind. Unfortunately, in practice, the flocculation ability may get lost after several repitches. Flow cytometry was employed to analyze glucose and mannose structures of the cell surface by application of fluorescent lectins. Validation of the expression of the flocculin genes Lg-FLO1, FLO1, FLO5, and FLO9 was carried out using microarray techniques. SDS-PAGE, western blot, and ESI-MS/MS analyses served to isolate and determine yeast cell flocculins. Mannose and glucose labeling with fluorescent lectins allowed differentiating powdery and flocculent yeast cells under laboratory conditions. Using microarray techniques and proteomics, the four flocculation genes Lg-FLO1, FLO1, FLO5, FLO9, and the protein Lg-Flo1p were identified as factors of major importance for flocculation. The expression of the genes was several times higher in flocculent yeast cells than in powdery ones. Flow cytometry is a fast and simple method to quantify the proportions of powdery and flocculent yeast cells in suspensions under defined cultivation conditions. However, differentiation under industrial conditions will require mRNA and protein expression profiling.
AB - The ability of brewing yeast to flocculate is an important feature for brewing of qualitatively good beer. Flocculation involves two main cell wall structures, which are the flocculation proteins (flocculins) and mannans, to which these flocculins bind. Unfortunately, in practice, the flocculation ability may get lost after several repitches. Flow cytometry was employed to analyze glucose and mannose structures of the cell surface by application of fluorescent lectins. Validation of the expression of the flocculin genes Lg-FLO1, FLO1, FLO5, and FLO9 was carried out using microarray techniques. SDS-PAGE, western blot, and ESI-MS/MS analyses served to isolate and determine yeast cell flocculins. Mannose and glucose labeling with fluorescent lectins allowed differentiating powdery and flocculent yeast cells under laboratory conditions. Using microarray techniques and proteomics, the four flocculation genes Lg-FLO1, FLO1, FLO5, FLO9, and the protein Lg-Flo1p were identified as factors of major importance for flocculation. The expression of the genes was several times higher in flocculent yeast cells than in powdery ones. Flow cytometry is a fast and simple method to quantify the proportions of powdery and flocculent yeast cells in suspensions under defined cultivation conditions. However, differentiation under industrial conditions will require mRNA and protein expression profiling.
U2 - 10.1002/cyto.a.20661
DO - 10.1002/cyto.a.20661
M3 - Journal article
C2 - 19072835
SN - 1046-7386
VL - 75
SP - 140
EP - 147
JO - Cytometry. Part A : the journal of the International Society for Analytical Cytology
JF - Cytometry. Part A : the journal of the International Society for Analytical Cytology
IS - 2
ER -