Monday, March 18, 2019

Genetics of Sourness

In a Cosmos article, the sourness of fruits are discussed and originates from the acidity of the vacuole. The vacuole is somewhat acidic due to the fact that hydrogen ions are pumped into it. The more hydrogen ions that are pumped, the more acidity. Citrus fruit have varieties that express gees CitPH1 and CitPH5 which encode for transporter proteins that amplify the pumping of ions increasing the concentrations. These genes were had an reduced expression in sweet or low acidic  like fruits. This can be beneficial to breeders for tastier fruits.
I love sour fruits so I was intrigued to read this article. I had learned that the purpose of a vacuole was for storage of different of nutrients, toxins, and aids in hydrostatic pressure. However, I was informed through this article that the sourness is derived from the amount of hydrogen ions are being pumped into it the organelle.  


  1. I found it very interesting to learn that the level of sourness in fruits is determined by the amount of pumped in hydrogen ions! The two genes, CitPH1 and CitPH5 code for proteins that can increase the pumping process. It is amazing that they can then determine how sour a fruit is by controlling the speed of pumped hydrogen ions.

  2. It was very interesting reading that how sour a fruit is because of the CitPH1 and CitPH5 gene. Personally I dislike super sour fruit or foods in general, I wonder if we have some type of gene that allows us to tolerate certain flavors or food types. it would be interesting to see if we have anything in our coding that prevents us from liking certain things.