Coffee has become an integral part of diet for almost everyone of us. While some drink it just for the matter of taste, many others use it get their mind alert when they feel drowsy, sleepy and lethargic.
Every second, more than 26,000 cups of coffee is drunk worldwide. Coffee contains a psychoactive substance called caffeine which helps in making our mind alert and active by decreasing the adenosine level in the brain. Excess presence of adenosine in the brain makes people feel lazy and sleepy.
There are many sources of caffeine. Many get it fix in tea, while others continue to drink mate, brewed from the yerba mate plant in South America. Cacao plants also produce caffeine. Hence, mild dose of caffeine can also be get from chocolates.
Caffeine is a form of drug which is the result of plant evolution that undergone for millions of years. Despite we have huge dependence on caffeine, scientists know very little about these psychoactive substance.
To find the crucial leads about its origin, an international team of scientists carried genome sequencing of Coffea canephora, which is the main source of coffee beans.
The sequencing of the genome helped scientists reconstruct how coffee got biochemical equipment that helped in making of caffeine.
Caffeine began in coffee plants as a precursor compound known as xanthosine. An enzyme made by coffee plant chops off a hanging atoms’ arm from the xanthosine and a second enzyme adds an atoms cluster at another spot. The coffee plant uses two different additional enzymes to add another two additional clusters. The conclusion of this process leads to the conversion of xanthosine into caffeine.
Scientists say the caffeine-building enzymes belong to an enzymes’ group called N-methyltransferases, which is found in all plants.
“They are all descendants of a common ancestor enzyme that started screwing around with xanthosine compounds,” said study co-author Victor A. Albert, an evolutionary biologist at the University at Buffalo.
The findings of the new study were published on Thursday in the journal Science.