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Specialty Chemistry Forums => Biochemistry and Chemical Biology Forum => Topic started by: NewtoAtoms on April 04, 2009, 04:49:32 PM

Title: What is the function of pyrophosphate group in isoprenoid biosynthesis?
Post by: NewtoAtoms on April 04, 2009, 04:49:32 PM

What is the most important function of the pyrophosphate group in isoprenoid biosynthesis?

a.  strongly acidic group and good proton donor
b.  good leaving group
c.  good nucleophile
d.  good electrophile
e.  ability to stablize an anion on the 'a' carbon

I am leaning toward 'c' as the correct answer, can anyone give me a reason as to another choice?

Thank you Biochemists.

Newtoatoms

Title: Re: What is the function of pyrophosphate group in isoprenoid biosynthesis?
Post by: NewtoAtoms on April 04, 2009, 04:54:29 PM

pardon me, I meant to write 'b' is the correct answer, because I believe that pyrophosphate groups in isoprenoid biosynthesis are good leaving groups, which as I believe is the final stage in terpene biosynthesis. Am I correct?

Title: Re: What is the function of pyrophosphate group in isoprenoid biosynthesis?
Post by: Wreath on April 06, 2009, 04:18:39 AM

I would agree with "b", pyrophosphate definitely is a good leaving group. When you take ATP for example, for some energetic reasons it´s nearly always the pyrophosphate which is cut off, not only phosphate. So I would expect the same in isoprenoid biosynthesis.