Can anyone make a simple explanation on how translocation( protein synthesis) occurs as I find it a bit overwhelming. I know it but I can't explain the steps that well.
There are four ways of transport in total. After searching for pictures in the internet, I guess its the best to give you a concrete explanation by sec-dependent-pathway .
By this translocation, the polypeptides are incomplete (that is why COOH and NH4 are at the ends). The preprotein is transporting through the (plasma) membrane during it is synthesised in Ribosomes. The proteins SecA and SecB are proteins, they are the so called ways of translocation, that is to say the preprotein is following these proteins to come out of the membrane. To get this preprotein through the membrane, energy is released in cytoplasm (ATP is breaking down to ADP). Thanks to this released energy, the preprotein is capable of getting through the membrane by another protein (SecYG).*
Hope that helps you to get an understanding for that. *