A new family of rhamnogalacturonan lyases contains an enzyme that binds to cellulose

The Two DUF642 At5g11420 and At4g32460-Encoded Proteins Interact In Vitro with the AtPME3 Catalytic Domain

“…The presence of these modules has been described in enzymes from bacteria that hydrolyse hemicelluloses and pectins to degrade the plant cell wall (Kellet et al, 1990;Mc Kie et al, 2001). The function of these modules appears to be related to a precise targeting to polymers in specific regions of plant cell walls during developmental processes.…”

Biochemical Characterization and Overexpression of an Endo-rhamnogalacturonan Lyase from Penicillium chrysogenum

“…Based on substrate specificity and mode of action, rPcRGL4A can be classified as an endo-acting RG lyase (EC 4.2.2.23). Of the RG lyases reported to date, only three enzymes including those from A. aculeatus [12,13], P. cellulosa [17], and B. subtilis [20] have been confirmed as endo-acting RG lyases based on analysis of their reaction products. PcRGL4A is the second endo-acting enzyme belonging to PL4, to be identified.…”

“…In contrast, divalent ions are essential for all RG lyases belonging to PL11. The P. cellulosa endo-RG lyase [17] and the C. cellulolyticum RG lyase [18] have an essential requirement for Ca 2? .…”

“…Based on the final major products, rPcRGL4A seems to be similar to the A. aculeatus RG lyase. RG lyases from P. cellulosa [17] and C. cellulolyticum [18] require Gal decoration of the RG backbones for degradation. The observation that DGR4 and DGR6 are released from RG-AG incubated with rPcRGL4A indicates that Gal decoration is not essential for this enzyme.…”

“…Several RG lyases have since been isolated and classified into two polysaccharide lyase families (PL), PL4 and PL11, based on their amino acid sequences. PL4 includes RG lyases from A. aculeatus [11][12][13][14], Erwinia chrysanthemi [15], and Aspergillus sojae [16]; and PL11 includes RG lyases from Pseudomonas cellulosa [17], Clostridium cellulolyticum [18], Bacillus subtilis [19][20][21], and Bacillus licheniformis [22]. However, the enzymatic characteristics of the RG lyases from A. aculeatus and B. subtilis are the only ones studied in details.…”