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I haven't been able to find anything that tells me how much ATP is needed for DNA replication, transcription, and translation in humans, just papers that mention ATP used in those processes.

I need to know how much ATP is needed for these processes because once my cell from scratch is alive I feed each cell 50 nanograms of glucose which yields 5 trillion ATP. If I use these numbers plus the numbers for other metabolic processes I get roughly the amount of ATP needed per cell before mitosis. If I know this then I will know if I need to feed my cells more glucose or if 50 nanograms is enough.

So how much ATP is needed for DNA replication, transcription, and translation? I want it in terms of per nucleotide and per amino acid so that I can multiply that by the amount of DNA total, amount of DNA in any given gene, and amount of amino acids in any given protein.

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    $\begingroup$ This is difficult to answer. Do you wish to include the ATP required to synthesize nucleobases, nucleoside triphosphates, amino acids, charged tRNA, etc? $\endgroup$
    – canadianer
    Commented Jun 1, 2015 at 4:18
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    $\begingroup$ I have given a rough answer and you can go into finer details (like accounting for NAD). You have not done any research towards the question and I am inclined to close the question. $\endgroup$
    – WYSIWYG
    Commented Jun 1, 2015 at 5:04
  • $\begingroup$ The information you provide is not nearly enough to figure out the energy needs of a cell before mitosis. You need to measure at least glucose uptake, lactate release and oxygen consumption, and do growth curves. Every cell line is different, so you need data on your cells. See ncbi.nlm.nih.gov/pubmed/14697210 and ncbi.nlm.nih.gov/pubmed/5817088. But you don't need to know this just to culture cells --- as long as they grow and look healthy, and the medium pH is not to low, they have enough glucose. $\endgroup$
    – Roland
    Commented Jun 1, 2015 at 5:40
  • $\begingroup$ Culture media for mammalian cells usually contain 1 to 4 gram/l. For example, when 10^6 cells are seeded on a 10 cm dish, you could grow them to about 10^7 for several days using 10 ml culture medium. For some cells you might have to replace medium with fresh one once before they reach 10^7 cells. You could know how much cells need glucose practically. When you have pyruvate in media, it goes TCA cycle so that glucose is not only the source of ATP. $\endgroup$
    – 243
    Commented Jun 1, 2015 at 5:58
  • $\begingroup$ In addition, ATP is required for sugar modification of proteins, protein phosphorylation, and probably amino acid and lipid synthesis as well as mechanical cell movement, vesicle transport, chromosome segregation and ... what else... $\endgroup$
    – 243
    Commented Jun 1, 2015 at 6:05

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For DNA replication and transcription you need NTPs. In a dsDNA purine content will be same as pyrimidine content. I am considering that all nucleotides are synthesized de novo which would consume more ATP than getting nucleotides from the salvage pathway.

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Fig 1: Pyrimidine synthesis. Taken from Wikipedia.

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Fig 2: Purine synthesis. Taken from Wikipedia.

CTP synthesis requires one extra ATP:

UTP + Glutamine + ATP + H2O → CTP + ADP + Pi

UTP synthesis requires 2 (Step 1; Fig 1) + 1 (Step 5; Fig 1: PRPP requires 1 ATP to form) +
2 (UMP → UTP) = 5 ATPs

CTP requires 6 ATPs

GTP requires 8 ATPs (Fig 2) (ATP synthesis would also require 8 ATPs but for simplicity let us assume that ATP is already present).

Conversion of dNTP from NTP requires thioredoxin which in turn requires NADP but let us forget that.

Assuming a 50% GC content one base pair of DNA would require in an average 10 ATPs (assume a stretch of 4nt — ACTG, this would require 1+6+5+8 ATPs; i.e. 5 ATPs per nt; 10 ATP per bp)

For RNA the ATP consumption would be 5 ATPs per nt.

For protein synthesis, for every codon, the elongation factor requires one molecule of GTP and aminoacyl-tRNA synthetase requires 1 molecule of ATP. So the net consumption per amino acid would be 9 ATPs.

I am ignoring the initiation reaction that also requires ATP to phosphorylate the initiation factor. Also, I assume that amino acids are obtained from diet and are not synthesized by the organism.

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