Subcellular distribution of glycanases and related components in Ruminococcus albus SY3 and their role in cell adhesion to cellulose.
OBJECTIVE
To compare the subcellular distribution of glycanase-related components between wild-type Ruminococcus albus SY3 and an adhesion-defective mutant, to identify their possible contribution to the adhesion process, and to determine their association with cellulosome-like complexes.


RESULTS
Cell fractionation revealed that most of the cellulases and xylanases were associated with capsular and cell-wall fractions. SDS-PAGE and gel filtration indicated that most of the bacterial enzyme activity was not integrated into cellulosome-like complexes. The adhesion-defective mutant produced significantly less (5- to 10-fold) overall glycanase activity, and the 'true cellulase activity' appeared to be entirely confined to the cell membrane fractions. Antibodies specific for the cellulosomal scaffoldin of Clostridium thermocellum recognized a single 240 kDa band in R. albus SY3.


CONCLUSIONS
The adhesion-defective mutant appeared to be blocked in exocellular transport of enzymes involved in true cellulase activity. A potential cellulosomal scaffoldin candidate was identified in R. albus SY3.


CONCLUSIONS
Several glycanase-related proteins and more than one mechanism appear to be involved in the adhesion of R. albus SY3 to cellulose.
Miron
J
J
Metabolic Unit, The Volcani Center, Bet Dagan, Israel. jmiron@actcom.co.il
Jacobovitch
J
J
Bayer
E A
EA
Lamed
R
R
Morrison
M
M
Ben-Ghedalia
D
D
D001422:Bacterial Adhesion; D001426:Bacterial Proteins / Q000378:metabolism*; D002482:Cellulose / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D006026:Glycoside Hydrolases / Q000235:genetics / Q000378:metabolism*; D006095:Gram-Positive Cocci / Q000201:enzymology* / Q000502:physiology / Q000648:ultrastructure; D009154:Mutation; D015388:Organelles / Q000502:physiology; D013347:Subcellular Fractions / Q000378:metabolism
D001426:Bacterial Proteins; D002482:Cellulose; D006026:Glycoside Hydrolases; C020668:glycanase