DNA Structure

by Tom Semmelroth

 

Visualizing life. Easy to say. But there is such plenty around us, one might feel overcome to choose. Every corner is filled with thousands of life forms, from the spider across the room to the microscopic life forms humankind is not able to see, floating around in the air right in front of you…

So let´s start small. Very small. With something we all have in common:

 

DNArotateting

 

Deoxyribonucleic Acid – The blueprint of any activity that can take place in any cell of any rather complex living organism. And every cell has one.

In this tremendous archive there are thus many informations stored that the DNA of a single cell, when unwinded, would form a really thin thread of about 2 meters length.

To cope with that storage issue, DNA forms an interesting structure, the chromatin, worth to take a closer look at:

Nucleotid

In the picture above you can see a nucleotid. It forms because the negatively loaded DNA combines with the bunch of positively charged histon proteins

DNAandHistome

 

In certain cell-types this 11nm-Fibre of DNA wrapped around Histone Octamers adds up with another Histon, the so called h1-Protein and folds up into the 30nm-Fibre.

30nmFibreTop 30nmFibreSolenoid 30nmFibreSide