A PHYLOGENETIC COMPARISON AND CLASSIFICATION OF LMCO SEQUENCES RETAINED FROM SOIL METAGENOME

Monika Zielińska

Abstract

Laccases (EC 1.10.3.2) belong to the family of multicopper oxidases (MCOs) and have the ability to oxidise various phenolic and nonphenolic compounds. In recent years, interest in bacterial laccases has increased because they have more favourable reaction features when compared to fungal laccases, such as their thermostability, alkaline pH, short acquisition time and simple overexpression system, making them highly desirable for industry. There is increasing molecular evidence that laccase-like multicopper oxidases (LMCOs) are widely distributed in bacteria. In this study, a total of 228 sequences of 3-domain LMCOs from a metagenome were used for phylogenetic analysis. A BLAST analysis and the reconstruction of the phylogenetic tree allowed to distinguish several LMCO sequence clusters, such as Alphaproteobacteria, Gammaproteobacteria, Deltaproteobacteria, Acidobacteria, Actinobacteria, Bacteroidetes and a cluster of unclassified sequences. The results of the phylogenetic analysis also suggest that the bacterial class of Deltaproteobacteria may play an important role in the lignin degradation process.