Material recommendation: molecular biology for mathematicians and computer scientists
I have also come from purely non-Bio background (I am a Software/Electrical engineer who didn't study Bio even in his high-school).
As others have pointed out in comments above that Molecular Biology is a vast field. But if you want resources covering all the basics of Genetics/Molecular Genetics, then I can easily recommend the following to anyone (which are both easy to understand and very authentic ones):


Nature Scitable
Genetics by PS Verma, Agarwal, S Chand. 


There are other books like this one but they all are on bioinformatics/advanced and expect some knowledge of Molecular Biology. My recommendation (proved one) are above two. Best of luck!!