This work studied the six -galactosidases (BGALs) of the subfamily a1 of Arabidopsis, that have been proposed to
play important roles in the cell wall remodelling during plant development, although their precise functions are still
unknown. Knockout mutants bgal1, bgal2, bgal3, bgal4, bgal5, and bgal12 of Arabidopsis and their wild type (WT)
plants were analysed to determine their morphology and composition of their cell walls. The gas chromatography and
the Fourier transform infrared spectroscopy revealed differences between the mutants and their WT such as in the
proportions of glucose, galactose, or xylose in bgal2 and bgal4 and in cell walls polysaccharides in bgal1, bgal3, and
bgal5. However, these slight changes did not result in morphological variations during plant development. None of the
mutant seedlings displayed a clear reduction in β(1,4)-galactan content, analysed by immunolocalization. The absence
of significant phenotypic changes in the -galactosidase subfamily a1 mutants could indicate possible
-galactosidases functional redundancy. Future studies will focus on the construction of multiple mutants that help to
establish the precise function of each member of the -galactosidase subfamily a1.
