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Urease production of calcifying bacterium, Bacillus megaterium SS3 was enhanced by using response surface methodology (RSM) in current study. The preliminary screening by Plackett-Burman's design revealed that among the tested factors, glucose, urea and NaHCO3 significantly ( p < 0.05) enhanced the urease production. Further optimization of urease production by B. megaterium through RSM was achieved as 879 U mL−1 in the presence of glucose (21.7 g L−1), urea (21.1 g L−1) and NaHCO3 (1.9 g L−1) compared to 640 U mL−1 in unoptimized medium. The effect of different factors seems to promote the growth of bacterial isolate leading to improvement in urease production. As production of carbonates by ureolytic bacteria is dependent on urease enzyme, improvement in enzyme production enhanced the carbonate precipitation efficacy to 1.7-fold in optimized medium. Carbonic anhydrase production also increased from 120 U mL−1 to 190 U mL−1 in optimized medium. © 2016 Curtin University of Technology and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Modern civilization is facing the dichotomy of rapid development of infrastructure that makes concrete as most traded material on the earth other than water. However, the production of cement, key ingredient of concrete, releases roughly a tonne of CO 2 into the environment with each tonne of cement production. The environmental concerns and sustainability issues associated with cement and concrete necessitate alternative and better approach in the construction. Nature, on the other hand, has a plethora of examples of sustainable habitats such as coral reefs, silk webs and ant hills. Recent advances in biotechnology have great potential of emulating nature’s way of building in modern days infrastructures at a scale that would sustain increasing population. Further, many of the biological materials of nature, be it ceramics or polymeric composites formed in the process of biomineralization, provides basis for sustainable construction. This paper elaborates nature’s way of construction based on biomineralization and discusses the progress of different biological pathways for sustainable construction. Main milestones achieved have been identified and the effect of biological intervention on the properties of structural materials has been highlighted. Variety of applications of biomineralization based technology in the construction has been reported. The paper briefly documents the future directions of the technology. [ABSTRACT FROM AUTHOR]