Abstract
To search for enzymes that improve the efficiency of protoplast production in Tricholoma matsutake, Paenibacillus sp. MU1, which harbors degradation activity for the dried fruit body of T. matsutake, was isolated. The bacterial strain has the potential to degrade the cell wall of T. matsutake, which was isolated from a soil sample using medium including insolubilized fraction of T. matsutake fruit body as a sole nutrient source. The draft genome sequence of the bacterium comprised 36 contigs, totaling 6.6 Mbp, with an average length of 184,698 bp. Whole genome sequence data identified the strain as Paenibacillus sp. MU1. Among its degrading activities, the bacterial α-1,3-glucanase (Mu1Agl) was purified to homogeneity, and its enzymatic properties were characterized. Mu1Agl acts on mutan (α-glucan with α-1,3 and α-1,6 linkages), but other polysaccharides and oligosaccharides are not substrates. Mu1Agl exhibited maximum activity at 40ｰC at around pH 6.0 in phosphate buffer. The Mu1Agl gene was cloned with reference to mass spectrometry and whole genome analysis information. The deduced amino acid sequence showed high homology with discoidin domain-containing proteins or α-1,3-glucanase of P. glycanilyticus and other Paenibacillus species. These results indicated that Mu1Agl belongs to the minor group (Subgroup 3) of GH family 87.
