Removal of Ni2+ and Cd2+ by Surface Display of Polyhistidine on Bacillus subtilis Spore Using CotE Anchor Protein

Abstract

In this paper, we report removing heavy metal using Bacillus subtilis spore surface display system. We used CotE protein as an anchoring motif because of its high abundance and location in the outer coat layer. And we inserted His 12 (double histidine 6 tag) at the C-terminal end of anchoring motif. The proper expression of CotE-His 12 fusion protein (22.8 kDa) was confirmed by western blot. We confirmed the surface expression of the CotE-His 12 fusion protein using flow cytometry. We tried Ni 2+ and Cd 2+ adsorption with recombinant spore DB104 (pCotE-His 12) and DB104 spore. The amount of adsorbed Ni 2+ was 18.2 nmol/mg for DB104 spore and 82.4 nmol/mg for DB104 (pCotE-His 12) spore. In the case of Cd 2+ , the adsorbed amount was 32.6 nmol/mg for DB104 spore and 79.1 nmol/mg for DB104 (pCotE-His 12) spore. This means that our spore displayed His 12 system can be generally applied for the removal of various kind of heavy metals in the field.

Surface display system for probiotics and its application in aquaculture

“…2018), whole‐cell adsorbent (Kim et al . 2019; Wang et al . 2019a), biological fuel cells (Fishilevich et al .…”

Aptamer-Conjugated Polydiacetylene Colorimetric Paper Chip for the Detection of Bacillus thuringiensis Spores

“…The following are available online at http://www.mdpi.com/1424-8220/20/11/3124/s1, Figure S1: Microscopic images of Bacillus thuringiensis (a) and GYS medium cultured Bacillus thuringiensis spores (b). The formation of spores can be confirmed by shape difference, Figure S2: 1…”

“…To purify the evaporated residue, the material was extracted with ethyl acetate using a separation funnel, TCDA-NHS monomer was obtained as a white solid. 1 H nuclear magnetic resonance (NMR) (400 MHz, chloroform-d) δ ppm 0.86 (t, 3 H), 1.24-1.79 (m, 28 H), 2.22 (t, 4 H), 2.58 (t, 2 H), 2.81 (s, 4 H) (Figure S2).…”

“…Certain bacteria can form durable, self-protective spore structures that can survive under harsh conditions. Eliminating bacterial spores with conventional sterilization methods is very difficult because the spore structure can protect it from environmental stresses, including desiccation, high temperature, UV irradiation, enzymatic destruction by drugs and exposure to toxic chemicals [1]. Therefore, the simple and rapid detection of spores is a widespread concern in food safety.…”

Potential Application of Living Microorganisms in the Detoxification of Heavy Metals

“…Apart from MTs and PCs, a surprising array of novel metal-binding domains have been explored for their potential application in HM removal. For instance, three copper-binding peptides NRWHHLE, NAKHHPR, and SPHHGGW [147], two Cd-binding peptides polyhistidine His12 [148] and SynHMB [149], three Pb-binding proteins PbrR, PbrR691, and PbrD [150] were surface-expressed in different strains to adsorb HMs from the contaminated sites.…”