5.1.3.37 physiological function generation of a strain in which all the algE genes are inactivated by deletion (algE1-4 and algE1-7) or interruption (algE5). The shake flask-grown mutant strain produces a polymer containing less than 2% G (with periplasmic isoform algG still active), while wild-type alginates contain 25% G. Addition of proteases to growth medium results in a strong increase in the chain lengths of the alginates produced. The mutant strain is unable to form functional cysts. Single algE gene inactivations, with the exception of algE3, has no detected effect on cell growth, morphology or alginate structure 733738 5.1.3.37 physiological function generation of a strain in which all the algE genes are inactivated by deletion (algE1-4 and algE6-7) or interruption (algE5). The shake flask-grown mutant strain produces a polymer containing less than 2% G (with periplasmic isoform algG still active), while wild-type alginates contain 25% G. Addition of proteases to growth medium results in a strong increase in the chain lengths of the alginates produced. The mutant strain is unable to form functional cysts. single isoform AlgE3 insertion mutants produce alginates with a G content as low as 8%, and contain almost no GG diads 733738 5.1.3.37 physiological function non-polar isoform algG knockout mutants of are defective in alginate production 733928 5.1.3.37 physiological function an isoform algG deletion mutant produces predominantly an unsaturated disaccharide containing a 4-deoxy-L-erythro-hex-4-enepyranosyluronate residue at the nonreducing end and a mannuronic acid residue at the reducing end. The production of this dimer is the result of the activity of an alginate lyase, AlgL, whose in vivo activity is much more limited in the presence of AlgG. A strain expressing both an epimerase-defective and a wild-type epimerase produces two types of alginate molecules: one class being pure mannuronan and the other having the wild-type content of guluronic acid residues. This formation of two distinct classes of polymers in a genetically pure cell line can be explained if AlgG is part of a periplasmic protein complex 734063 5.1.3.37 metabolism biosynthetic pathway of alginate and the alginate structure involving the enzyme, overview 746698 5.1.3.37 physiological function in brown algae, the M/G ratio and the composition of blocks consisting of these residues varies based on several factors, including species, portion (blade, stipe, and rhizoid), season, growth conditions, and habitat. Analysis of expression and enzymatic characterization of brown algal MC5E(s) 746698 5.1.3.37 malfunction reducing the size of AlgE6 influences the epimerization of modified alginates in solution. The A-module from AlgE6 seems to be more affected than AlgE64 at higher degree of oxidation 747457 5.1.3.37 additional information the A-module is the minimal size for an active epimerase even though the active site is located in proximity of the N-terminus 747457 5.1.3.37 additional information the A-module is the minimal size for an active epimerase even though the active site is located in proximity of the N-terminus. AlgE1 is larger than AlgE6 and has two catalytic active modules (A1 and A2) 747457 5.1.3.37 evolution Ectocarpus contains a multigenic family of putative ManC5-Es. The genome sequence of Ectocarpus offers the opportunity to have access to a higher number of genes, and potentially proteins, 31 putative ManC5-E genes are analyzed. The ManC5-E family includes genes that are differentially regulated during the life cycle of Ectocarpus 747915