, lives in New Delhi. I think it must be TAJ MAHAL.because the construction price in 1632 was 32 million rupees. at that time india was super power in world. so if you compare 32millions rupees with today's rupees then taj must be most expensive.
The carbonic anhydrases (or carbonate dehydratases) form a family of enzymes that catalyze the rapid interconversion of carbon dioxide and water to bicarbonate and protons (or vice versa), a reversible reaction that occurs relatively slowly in the absence of a catalyst.
The mechanism of action of the mammalian carbonic anhydrase has been studied in depth. The enzyme employs a two-step mechanism: in the first step, there is a nucleophilic attack of a zinc-bound hydroxide ion on carbon dioxide; in the second step, the active site is regenerated by the ionisation of the zinc-bound water molecule and the removal of a proton from the active site.