Cis-Platin and Its Effects on DNA Replication

[Positron]

Before I ask my question, I would like to state that I am not a Biology student. I am actually a Chemistry student who has a small section on Biochemistry in his syllabus.

Now, my problem lies with part (ii).

Mechloroethamine obviously hold the DNA strands together and prevents the DNA helix from uncurling/unzipping. Hence, the very first stage in replication is impeded.

How cis-platin affects DNA replication is eluding me. I know that Guanine normally forms 3 hydrogen bonds with Cytosine. However, it seems to be forming only one hydrogen bond in this case.

Could someone prod me in the correct direction ?

[Positron]

bump

[JackBean]

http://www.ncbi.nlm.nih.gov/pubmed/18729380

[Positron]

That doesn't really answer the question above.

[canalon]

From http://en.wikipedia.org/wiki/Cisplatin
1- the dashed line appear to be no more than just a representation of the 3 H bond between G and C not an accurate representation.
2- Cis-platin do intra strand and interstrand crosslinking. Both interfere with replication (I suspect intrastrand crosslinking might even change the correct DNA structure) sterically and by prevent correct unzipping of the DNA double helix