Naming Nucleosides and Nucleotides - Online Tutor, Practice Problems & Exam Prep

Nucleosides consist of a nitrogenous base and a sugar, with pyrimidines ending in "idine" and purines in "osine." For RNA, uracil forms urodine, while DNA uses deoxy sugars, leading to names like deoxyadenosine. Nucleotides add a 5' monophosphate to nucleoside names. For example, urodine becomes uridine 5' monophosphate. Remember the one-letter codes: C, U, A, G for RNA and C, T, A, G for DNA, with "d" prefix for deoxyribonucleotides. Understanding these naming conventions is crucial for studying nucleic acids and their functions in biological systems.

Naming Nucleosides and Nucleotides Concept 1

Now, when it comes to naming nucleosides, we're going to say it's the name of the nitrogenous base with a suffix modifier. And remember, when it comes to our nitrogenous bases, we categorize them into two categories. Our pyrimidines, which is our single-ringed molecule, and then our purines, which is our double-ringed molecule. When it comes to pyrimidines, the ending changes to "idine", and for purines, when it's involved, the ending is "osine".

If we take a look here, we have an RNA nucleoside being created. Remember, RNA uses the nitrogenous base uracil. So here we have our ribosugar, and our uracil. When they connect together through a condensation reaction, we have the loss of water. This helps create the glycosidic bond right here between the nitrogen and the anomeric carbon. Here we would change the ending of the nitrogenous base, so now it's no longer uracil, it's "uridine". So, we have replaced the "acyl" or "uracil" part of this with "idine".

Over here, we have the DNA nucleoside. Remember, DNA uses 2-deoxyribose sugar instead of ribosugar like RNA. Here we have adenine. Again, we're going to have the creation of our glycosidic bond right here between the nitrogen and the anomeric carbon. Here, what we need to note is in addition to the suffix modifier, we have to use the prefix "deoxy" to designate that this carbon number 2 doesn't have an OH group, it has just an H. So here, the name would be "deoxy" and because it is a purine ring, the ending is "osine". So, it becomes "adenosine". So here, I kept this part here, and the "yne" portion became "osine". So, 2 OH, so it becomes "deoxyadenosine" as the name of this particular nucleoside. So, just remember these naming conventions when it comes to our different types of nucleosides.

Naming Nucleosides and Nucleotides Concept 2

Now remember that a nucleoside is just a precursor to a nucleotide. We learned that when it comes to nucleosides, the pyrimidine, we change the ending to "idine", and with the purine, we change the ending to "oside". Here, we're now looking at nucleotides. With nucleotides, we would just add 5' monophosphate to the end of the nucleoside name. So, just remember, if we're looking at just the nucleoside portion, it would have been "Uridine", but because we're adding the phosphate group to make a nucleotide, we add 5'-monophosphate. 5' because the phosphate is connecting to carbon 5'. Over here, we had deoxyadenosine because it was a deoxyribose sugar with our adenine nitrogenous base. That gave us "Deoxyadenosine" as the name, but because we're adding this phosphate group to our 5' carbon, we add 5' monophosphate to the end of the name. So, just remember, to be able to name these nucleotides, it's important to remember the naming conventions and rules for naming the given nucleoside. Once you know the name of the nucleoside, just add 5'-monophosphate to the end of the name.

Naming Nucleosides and Nucleotides Concept 3

Here, we're going to take a look at our naming summary. So we have our RNA and our DNA. Remember, the difference in bases is that for RNA, we use uracil, and for DNA, we use thymine. Now, here with the nucleoside, remember, when it comes to a pyrimidine, we change the ending to -idine. And when it's a purine involved as a nitrogenous base, the ending changes to -osine. So, if we take a look here, we have cytosine, uracil, adenine, and guanine, and then their nucleoside names. For the pyrimidines, we change them to -idine, so cytidine, uridine, and then for the purines, we change them to -osine, so adenosine, guanosine. With the nucleotide, all we do is we add 5'-monophosphate to the end of the name. So, it would be each of these with 5'-monophosphate to the end of the name. Remember, each one of these nitrogenous bases has a one-letter code for themselves. So cytosine is C, uracil is U, adenine is A, guanine is G. But here we're talking about the monophosphate version of them, so we'd have to add MP at the end for monophosphate. So these would be their abbreviations.

With DNA, we have here cytosine, thymine, adenine, and guanine. Remember, with DNA, we have to use the prefix of deoxy as well. So, that's the difference here. We have deoxy, but then the rest of the name is the same. Here, we have thymine and because thymine is a pyrimidine, it uses the ending -idine. Again, we have deoxy and deoxy. Just like RNA, once we introduce the phosphate group to the 5'-carbon, we add 5'-monophosphate to the end of the name. Here, the difference now, in addition to these small changes like deoxy, we'd have to add a lowercase 'd' to the front of the name to represent the deoxy component involved. Then, we would include the one-letter abbreviation for each of these nitrogenous bases. So, cytosine is C, thymine is T, adenine is A, guanine is G. And we're talking about the monophosphate version of them, the nucleotide version. So we'd write MP at the end. So, these will represent the abbreviations of each one of these nucleotides.

So, just remember the naming convention that you learned when it comes to nucleosides. And then when it comes to nucleotides, you add 5'-monophosphate to the other name. Remember the one-letter code for each of these nitrogenous bases? We add MP to the end of it to represent the monophosphate. If deoxyribonucleic acid is being used in the form of DNA, we add a lowercase 'd' to the front of the name. Right? So just remember these naming conventions and these naming summaries.

Naming Nucleosides and Nucleotides Example

Here it says, name the following nucleoside. Alright. So if we take a look at this image, we would see that on carbon number 2, there's the absence of an OH group, just an H here. So this means that we're dealing with DNA. With DNA, we have the prefix of deoxy. Next, they tell me, so we're going to say, this is our prefix deoxy. Next, we're going to say we're dealing with a 1-ring nitrogenous base. Right? So that means that we're dealing with a pyrimidine. And if we're dealing with a pyrimidine, that means the suffix, the ending, would have to be idine. And now, what we need to do is we need to figure out what our nitrogenous base is. If we take a look here, this looks like the beginnings or the base form of uracil, except we've added a methyl group here. Methyl group. Methyl group. So if we remember our different memory tools, meth, t h y means that we're dealing with thymine. So the base here is thymine. So putting it all together, deoxy would be the beginning of the name. Remember, the base is thymine, but we're going to change the ending to idine. So, Deoxythymidine will be the name of the given nucleoside presented within this example question.

Provide a name for the following nucleotide.

• A. uridine 5'-monophosphate
• B. cytidine 5’-monophosphate
• C. urisine 3'-monophosphate
• D. cytosine 5’-monophosphate

Draw a nucleotide structure for GMP.

Here it says we need to draw a nucleotide structure for GMP. Alright. So first of all, it says GMP. It does not say dGMP. If it had said d, that means we'll be dealing with a deoxyribose sugar. Because d is not there, we're dealing with a simple ribose sugar. So we draw ribose sugar. Carbon number 3 and 2, each have an OH group. MP Monophosphate, that means that carbon number 5, 5' has a phosphate group connected to it. Let's just add that. So here goes our phosphate group. And then G here is guanine, so we just have to draw what that looks like. Guanine here represents a purine so it's 2 fused rings. On the anomeric carbon, we're connected to the nitrogen, which is part of guanine. So here we're gonna draw it out, double bond here. We have a double bond here. We have our carbonyl connected to our NH, connected to another carbonyl. Well, actually, no. Not a carbonyl, an NH2 group connected to nitrogen, closing in to make that 6 membered ring, and we have our double bond here. So this would be the structure of our GMP. We're dealing with Guanine 5' monophosphate. We're dealing with, the guanine version. Because this is a purine, it will be a guanosine 5' monophosphate. OK. So MP for the 5' monophosphate part, it is a purine ring, so the ending of the nitrogenous base changes to oside. Right. So this would be its formal name. This would be its abbreviation. This would be its structure. So keep in mind each of these conventions that we learned. If you don't remember how to draw out the nitrogenous base, make sure you go back on our topic on nitrogenous bases where we talk about different memory tools and tricks to help you remember the structures of these different types of nitrogenous bases.

Here’s what students ask on this topic:

What is the difference between a nucleoside and a nucleotide?

A nucleoside consists of a nitrogenous base (either a purine or pyrimidine) attached to a sugar molecule (ribose in RNA or deoxyribose in DNA). A nucleotide, on the other hand, is a nucleoside with one or more phosphate groups attached to the 5' carbon of the sugar. For example, adenosine is a nucleoside, while adenosine 5'-monophosphate (AMP) is a nucleotide. Understanding this distinction is crucial for studying nucleic acids and their roles in biological systems.

How do you name nucleosides and nucleotides in RNA and DNA?

Nucleosides in RNA and DNA are named based on their nitrogenous bases. For pyrimidines (cytosine, uracil, thymine), the suffix changes to 'idine' (e.g., cytidine, uridine). For purines (adenine, guanine), the suffix changes to 'osine' (e.g., adenosine, guanosine). In DNA, the prefix 'deoxy' is added (e.g., deoxyadenosine). Nucleotides are named by adding '5'-monophosphate' to the nucleoside name (e.g., uridine 5'-monophosphate, deoxyadenosine 5'-monophosphate). The one-letter codes for RNA are C, U, A, G, and for DNA, they are C, T, A, G, with a 'd' prefix for deoxyribonucleotides.

What are the one-letter codes for nucleotides in RNA and DNA?

The one-letter codes for nucleotides in RNA are C (cytosine), U (uracil), A (adenine), and G (guanine). For DNA, the one-letter codes are C (cytosine), T (thymine), A (adenine), and G (guanine). When referring to deoxyribonucleotides in DNA, a lowercase 'd' is added as a prefix (e.g., dC for deoxycytidine monophosphate).

How do you name a nucleotide when a phosphate group is added?

To name a nucleotide, you start with the nucleoside name and add '5'-monophosphate' to indicate the addition of a phosphate group at the 5' carbon. For example, uridine (a nucleoside) becomes uridine 5'-monophosphate (a nucleotide). For DNA nucleotides, you also include the 'deoxy' prefix and a lowercase 'd' (e.g., deoxyadenosine becomes deoxyadenosine 5'-monophosphate, abbreviated as dAMP).

What is the naming convention for nucleosides with purine and pyrimidine bases?

Nucleosides with pyrimidine bases (cytosine, uracil, thymine) end in 'idine' (e.g., cytidine, uridine, thymidine). Nucleosides with purine bases (adenine, guanine) end in 'osine' (e.g., adenosine, guanosine). For DNA nucleosides, the prefix 'deoxy' is added (e.g., deoxyadenosine, deoxyguanosine). These naming conventions help differentiate between the types of nitrogenous bases and the sugars they are attached to.