It is a less invasive surgery, so your recovery time is shorter and easier than with mastectomy. Lumpectomy has a few potential disadvantages: You are likely to have 5 to 7 weeks of radiation therapy, 5 days per week, after lumpectomy surgery to make sure the cancer is gone.
DNA: Double Helix. The secondary structure of DNA is actually very similar to the secondary structure of proteins. The protein single alpha helix structure held together by hydrogen bonds was discovered with the aid of X-ray diffraction studies. The X-ray diffraction patterns for DNA show somewhat similar patterns.
Proteins of DNA Replication. 1  DNA Helicases-These proteins bind to the double stranded DNA and stimulate the separation of the two strands. 2  DNA single-stranded binding proteins-These proteins bind to the DNA as a tetramer and stabilize the single-stranded structure that is generated by the action of the helicases. The DNA molecule is unwound and prepared for synthesis by the action of DNA gyrase, DNA helicase and the single-stranded DNA binding proteins. 2  A free 3'OH group is required for replication, but when the two chains separate no group of that nature exists.