Production of none germinate spore ghost from a novel marine Bacillus with thermostable laccase activity

Abstract

Laccases are effective biocatalysts for various biotechnological applications. Treatment of effluents containing phenol components such as toluene using fungal laccases is usually limited to the acid to neutral pH range and moderate temperatures. In this research, severalBacilli sp., were isolated from marine environment in toluene enriched media in purpose to obtain high laccase activities in spore forming bacteria. Among all the identified isolates,Bacillus sp. XJT-7 removed more toluene in contrast with other strains. The isolatedBacillus grew on toluene as the sole source of carbon and energy with maximum laccase activity and compared with Bacillus sphaericus (ATCC: CCM2177) as a standard strain which has laccase activity without any growth on toluene. Laccase activities in spore ghosts which mislay their germination power by heat shock have been investigated. The results showed that the vegetative cell free spore ghosts had thermostable laccase activities and remained active at 100°C shock. These heated spores (spore ghosts) are useful in biodegradation due to a high laccase activity. The image of Atomic Force Microscopy (AFM) showed that the spore ghosts have 50 nm pores which are good for drug delivery and drug synthesis with laccase activity without any chances for having spore germination. Key words: Bacillus sp., spore ghost, Laccase, atomic force microscopy (AFM).