6533b85efe1ef96bd12bfe0d
RESEARCH PRODUCT
High yield recombinant production of a self-assembling polycationic peptide for silica biomineralization.
Stephan HobeSandor NietzscheChristian ZerfaßSandra BraukmannHarald Paulsensubject
chemistry.chemical_classificationDiatomsOligopeptideIon chromatographyPeptideIsomerasemedicine.disease_causeSilicon DioxideRecombinant Proteinslaw.inventionchemistry.chemical_compoundchemistryBiochemistrylawmedicineRecombinant DNAEscherichia coliCyanogen bromideEscherichia coliOligopeptidesBiotechnologyBiomineralizationdescription
We report the recombinant bacterial expression and purification at high yields of a polycationic oligopeptide, P5S3. The sequence of P5S3 was inspired by a diatom silaffin, a silica precipitating peptide. Like its native model, P5S3 exhibits silica biomineralizing activity, but furthermore has unusual self-assembling properties. P5S3 is efficiently expressed in Escherichia coli as fusion with ketosteroid isomerase (KSI), which causes deposition in inclusion bodies. After breaking the fusion by cyanogen bromide reaction, P5S3 was purified by cation exchange chromatography, taking advantage of the exceptionally high content of basic amino acids. The numerous cationic charges do not prevent, but may even promote counterion-independent self-assembly which in turn leads to silica precipitation. Enzymatic phosphorylation, a common modification in native silica biomineralizing peptides, can be used to modify the precipitation activity.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2015-04-01 | Protein expression and purification |