A novel Streptomyces strain isolated by functional bioprospecting for laccases

In discovering novel laccase enzymes with interesting catalytic and stability properties, there is still scope for improvement in exploring new sites in Algeria. The bio-prospecting approach allowed the isolation of a novel strain, Streptomyces sp. HBD30 from the Agrioun River, northern Algeria. Following a functional approach, two laccases (LacI and LacII) were purified and characterised, showing appealing properties as thermostable enzymes, and oxidised typical phenolic and non-phenolic substrates with a higher affinity towards syringaldazine, followed by 2,6-dimethoxyphenol and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid). Further analyses revealed that the Streptomyces sp. HDB30 genome contained an array of genes coding for carbohydrate active enzymes (CAZome) and lignin-degrading enzymes to degrade lignocellulose. In addition to enlarging the repertoire of thermostable laccases, this study uncovered the metabolic potential of a new Streptomyces strain, which is useful for a wide range of applications.