Amy63, a novel type of marine bacterial multifunctional enzyme possessing amylase, agarase and carrageenase activities

Abstract

A multifunctional enzyme is one that performs multiple physiological functions, thus benefiting the organism. Characterization of multifunctional enzymes is important for researchers to understand how organisms adapt to different environmental challenges. In the present study, we report the discovery of a novel multifunctional enzyme Amy63 produced by marine bacterium Vibrio alginolyticus 63. Remarkably, Amy63 possesses amylase, agarase and carrageenase activities. Amy63 is a substrate promiscuous α-amylase, with the substrate priority order of starch, carrageenan and agar. Amy63 maintains considerable amylase, carrageenase and agarase activities and stabilities at wide temperature and pH ranges, and optimum activities are detected at temperature of 60 °C and pH of 6.0, respectively. Moreover, the heteroexpression of Amy63 dramatically enhances the ability of E. coli to degrade starch, carrageenan and agar. Motif searching shows three continuous glycosyl hydrolase 70 (GH70) family homologs existed in Amy63 encoding sequence. Combining serial deletions and phylogenetic analysis of Amy63, the GH70 homologs are proposed as the determinants of enzyme promiscuity. Notably, such enzymes exist in all kingdoms of life, thus providing an expanded perspective on studies of multifunctional enzymes. To our knowledge, this is the first report of an amylase having additional agarase and carrageenase activities.

Multifunctional Alkalophilic α-Amylase With Diverse Raw Seaweed Degrading Activities

“…For example, the multifunctional amylase Amy440 produced by Aquimarina agarilytica ZC1 was reported to show amylase and agarase activities (Lin et al 2017); the multifunctional amylase Amy63 produced by Vibrio alginolyticus 63 was reported to show amylase, agarase. and carrageenase activities (Liu et al 2016); and the multifunctional amylase Amy19 produced by Bacillus BI-19 was reported to show agarase, carrageenase, and cellulase activities (Li et al 2019). To the best of our knowledge, Amy2587 is the rst multifunctional enzyme found to have ve enzyme activities at the same time.…”

“…Traditionally, enzymes were believed to have high selectivity or speci city for their substrates and reactions (Dan 2020). However, enzymes with cross-reactivity or promiscuity have been discovered and characterized (Liu et al 2016; Khersonsky et al 2006;Pocker and Stone 1965), and increasing numbers of multifunctional enzymes that can hydrolyze various substrates to produce oligosaccharides have been reported.…”

Formation of cadmium sulfide nanoparticles mediates cadmium resistance and light utilization of the deep‐sea bacterium Idiomarina sp. OT37‐5b

“…OT37‐5b. The procedure was carried out as described previously with minor modification (Liu et al ., 2016). The bismuth strained proteins were manually excised from the gel and digested with trypsin.…”

Extracellular expression of agarase rAgaM1 in Bacillus subtilis and its ability for neoagaro‐oligosaccharide production

“…Directly using the supernatant of fermentation broth containing agarase without protein purification is an effective method to save these costs, although rare relevant works are reported until now. Moreover, crude agar and agarose were used as the substrates to produce the oligosaccharides in these previous studies , thereby increasing the cost of industrial production. In our previous work , a GH16 β‐agarase gene, agaM1 (GenBank accession number: MG280837), was expressed in E. coli cells and was further purified for enzymatic assays.…”