Abstract
In the present study, the properties of calcium carbonate mineralization and urease and carbonic anhydrase activities of Bacillus amyloliquefaciens U17 isolated from calcareous soil of Denizli (Turkey) were analyzed. CaCO3 was produced in all growth phases. Strain U17 showed 0.615 ± 0.092 µmol/min/mg urease enzyme activity in calcium mineralization medium and 1.315 ± 0.021 µmol/min/mg urease enzyme activity in Luria-Bertani medium supplemented with urea, whereas it showed 36.03 ± 5.48 nmol/min/mg carbonic anhydrase enzyme activity in CaCO3 precipitation medium and 28.82 ± 3.31 nmol/min/mg carbonic anhydrase enzyme activity in Luria-Bertani medium supplemented with urea. The urease B protein expression level of strain U17 was detected by western blotting for the first time. The produced CaCO3 crystals were analyzed by X-ray diffraction, X-ray fluorescence, confocal RAMAN spectrophotometer, scanning electron microscopy, and electron probe microanalyzer for the evaluation of their morphological and elemental properties. Rhombohedral vaterite and layered calcite crystals were clearly detected and verified by mineralogical analyses. All these results showed that strain U17 can be used in many engineering and geological applications due to its CaCO3 precipitation ability.
Highlights
Biomineralization is the process of synthesis of mineral materials by organisms
The incubation period was started with CPM adjusted to initial pH 6.50 and slight changes in pH occurred after incubation, and it kept increasing throughout the 14 days of the incubation period
Our previous studies demonstrated that increasing incubation time is very effective in transforming vaterite crystals to calcite, and Paenibacillus favisporus U3 isolated from Denizli (Turkey) had the maximum CaCO3 precipitation among the tested strains and it was utilized for geotechnical studies (Akyol et al, 2017)
Summary
Biomineralization is the process of synthesis of mineral materials by organisms. It is commonly acknowledged that prokaryotes are more capable than other organisms in biomineralization processing (Zavarzin, 2002). One of the well-known examples of bacterial biomineralization is calcium carbonate (CaCO3) precipitation and it is well established that many bacteria have the capability of producing various forms of CaCO3 in a different environment Anhydrous polymorphs such as calcite, aragonite, and vaterite and hydrated crystalline forms such as monohydrocalcite and ikaite are produced as a result of the biomineralization of CaCO3 (Rieger et al, 2007; Gower, 2008; Gebauer et al, 2010), calcite and vaterite are the most common forms of CaCO3 (Rodriguez-Navarro et al, 2007; González-Muñoz et al, 2010). While vaterite is rarely found in geological settings, it is a fundamental precursor in many of the carbonate formation processes (Wang and Becker, 2009)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
