Àá½Ã¸¸ ±â´Ù·Á ÁÖ¼¼¿ä. ·ÎµùÁßÀÔ´Ï´Ù.
KMID : 0545120200300030404
Journal of Microbiology and Biotechnology
2020 Volume.30 No. 3 p.404 ~ p.416
Complete Genome and Calcium Carbonate Precipitation of Alkaliphilic Bacillus sp. AK13 for Self-Healing Concrete
Jung Yoon-Hee

Kim Won-Jae
Kim Wook
Park Woo-Jun
Abstract
Bacteria that are resistant to high temperatures and alkaline environments are essential for the biological repair of damaged concrete. Alkaliphilic and halotolerant Bacillus sp. AK13 was isolated from the rhizosphere of Miscanthus sacchariflorus. Unlike other tested Bacillus species, the AK13 strain grows at pH 13 and withstands 11% (w/v) NaCl. Growth of the AK13 strain at elevated pH without urea promoted calcium carbonate (CaCO3) formation. Irregular vateritelike CaCO3 minerals that were tightly attached to cells were observed using field-emission scanning electron microscopy. Energy-dispersive X-ray spectrometry, confocal laser scanning microscopy, and X-ray diffraction analyses confirmed the presence of CaCO3 around the cell. Isotope ration mass spectrometry analysis confirmed that the majority of CO3 2- ions in the CaCO3 were produced by cellular respiration rather than being derived from atmospheric carbon dioxide. The minerals produced from calcium acetate-added growth medium formed smaller crystals than those formed in calcium lactate-added medium. Strain AK13 appears to heal cracks on mortar specimens when applied as a pelletized spore powder. Alkaliphilic Bacillus sp. AK13 is a promising candidate for self-healing agents in concrete.
KEYWORD
Bacillus species, microbially-induced calcium carbonate precipitation, calcium acetate, isotope ratio mass spectrometer, X-ray diffraction, crack healing
FullTexts / Linksout information
Listed journal information
SCI(E) MEDLINE ÇмúÁøÈïÀç´Ü(KCI)