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## DNA/RNA

Discussion of all aspects of biological molecules, biochemical processes and laboratory procedures in the field.

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### DNA/RNA

Hi....A couple of questions..help....

If a structural gene contains 300 DNA nucleotides, how many amino acids will be used in the protein synthesis process?

If a protein has 150 amino acids, how many DNA nucleotides would make up the structural gene?
Diana Timpano
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### Re: DNA/RNA

Diana Timpano wrote:Hi....A couple of questions..help....

If a structural gene contains 300 DNA nucleotides, how many amino acids will be used in the protein synthesis process?

If a protein has 150 amino acids, how many DNA nucleotides would make up the structural gene?

Pretty easy!!
No of amino acids= 300/3 = 100 amino acids
No of nucleotides= 150*3 = 450 nucleotides
Arty
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### Re: DNA/RNA

Arty wrote:
Diana Timpano wrote:Hi....A couple of questions..help....

If a structural gene contains 300 DNA nucleotides, how many amino acids will be used in the protein synthesis process?

If a protein has 150 amino acids, how many DNA nucleotides would make up the structural gene?

Pretty easy!!
No of amino acids= 300/3 = 100 amino acids
No of nucleotides= 150*3 = 450 nucleotides

if we don't go in details(stop codon...)?

zami'87.
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448 maximum if you include the start codon and stop codons.

biostudent84

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biostudent84 wrote:448 maximum if you include the start codon and stop codons.

I think if you really want to count stop codons (start codons are transcribed) you get these results
(300 nt - 1 non transcribed stop codon)= 99 aa
and (150aa + 1 non transcribed stop codon)x3= 453nt

Patrick

canalon
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What are the "n" and the "t" meaning in this example?

biostudent84

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biostudent84 wrote:What are the "n" and the "t" meaning in this example?

oopps "nt" stands for nucleotides (bases) as "aa" stands for amino acids.

Patrick

canalon
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I'd like to know where I got that number from and what the heck I was thinking.....

98 maximum if you count the start and stop codons.

Sorry.....

biostudent84

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biostudent84 wrote:I'd like to know where I got that number from and what the heck I was thinking.....

98 maximum if you count the start and stop codons.

Sorry.....

Start codons ARE transcribed, hence 99.

canalon
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They are? Thanks

biostudent84

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From what i know, start codons are transcripted, but if your protein does not begin with metionin then it is later removed
"As a biologist, I firmly believe that when you're dead, you're dead. Except for what you live behind in history. That's the only afterlife" - J. Craig Venter

MrMistery
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### INTRONS

r we forgetting something...
Oh yes...INTRONS
if the structural gene contains introns then the no. of aa reqd. for protein making is indeterminate !
or else if its a bacterial gene then my predecessors have already done the math.
Know thyself.

cytochromeP