当前位置： SCI文献检索 > JOURNAL OF BIOTECHNOLOGY期刊下所有文献 > Engineered biosealant strains producing inorganic and organic biopolymers.

Engineered biosealant strains producing inorganic and organic biopolymers.

Abstract：

:Microbiologically induced calcium carbonate precipitation (MICCP) is a naturally occurring biological process that has shown its potential in remediation of a wide range of structural damages including concrete cracks. In this study, genetically engineered microorganisms, capable of producing extracellular polymeric substances (EPSs) as well as inducing MICCP, were developed based on the assumption that the complex of inorganic CaCO(3) and organic EPS would provide a stronger matrix than MICCP alone as biosealant. In order to develop a recombinant biosealant microorganism, the entire Sporosarcina pasteurii urease gene sequences including ureA, ureB, ureC, ureD, ureE, ureF, and ureG from plasmid pBU11 were sub-cloned into the shuttle vector, pUCP18. The newly constructed plasmid, pUBU1, was transformed into two Pseudomonas aeruginosa strains, 8821 and PAO1, to develop recombinants capable of inducing calcite precipitation in addition to their own ability to produce EPS. Nickel-dependent urease activities were expressed from the recombinant P. aeruginosa 8821 (pUBU1) and P. aeruginosa PAO1 (pUBU1), at 99.4% and 60.9% of the S. pasteurii urease activity, respectively, in a medium containing 2mM NiCl(2). No urease activities were detected from the wild type P. aeruginosa 8821 and P. aeruginosa PAO1 under the same growth conditions. Recombinant Pseudomonas strains induced CaCO(3) precipitation at a comparable rate as S. pasteurii and scanning electron microscopy evidenced the complex of CaCO(3) crystals and EPS layers surrounding the cells. The engineered strains produced in this study are expected to serve as a valuable reference to future biosealants that could be applied in the environment. However, the pathogenic potential of P. aeruginosa, used here only as a model system to show the proof of principle, prevents the use of this recombinant organism as a biosealant. In practical applications, other recombinant organisms should be used.

journal_name

J Biotechnol

journal_title

Journal of biotechnology

authors

Bergdale TE,Pinkelman RJ,Hughes SR,Zambelli B,Ciurli S,Bang SS

doi

10.1016/j.jbiotec.2012.07.001

subject

Has Abstract

pub_date

2012-10-31 00:00:00

pages

181-9

issue

eissn

0168-1656

issn

1873-4863

pii

S0168-1656(12)00364-1

journal_volume

161

pub_type

杂志文章

在线工具

Engineered biosealant strains producing inorganic and organic biopolymers.