So now that we've talked about the first step of DNA cloning, which is making the recombinant DNA molecule in our previous lesson videos, in this video, we're going to talk about the second step of DNA cloning, which is transforming the recombinant DNA into bacteria. And so again, the second and final step of DNA cloning is to transform the recombinant DNA. Now, this term 'transform' is not used as you would use the term transform in your everyday language. In this context, the term transform is referring to the process of transformation. And transformation is the process that allows cells to directly uptake foreign DNA from their environment and allows them to obtain foreign DNA from their environment. For example, it allows them to obtain a cloning vector, such as a recombinant DNA molecule. And so organisms that have successfully transformed a recombinant DNA molecule are called transgenic organisms. And so a transgenic organism is an organism that has received and expressed the recombinant DNA molecule. And so the transgenic organism is going to have DNA that is going to come from a completely different source, a completely different species.

Now, scientists can use what are known as phenotypic markers, for example, antibiotic resistance, in order to confirm a positive transformation and confirm that the bacteria have successfully received the recombinant DNA molecule. And so we can get a better understanding of the process of transformation down below in our image. And in this example image, we're looking at creating a transgenic organism with antibiotic resistance by transformation of recombinant plasmid DNA. And so in this image down below, course, we know that in the first step of DNA cloning, we need to make the recombinant DNA, and that's what we're showing you here in this first part of the image. And so you can see that we've got the bacterial plasmid DNA over here and the gene of interest over here, which in this case is going to have an antibiotic resistance gene. And so of course if we want to create the recombinant DNA molecule, then we're going to need to use restriction enzymes to cut each of these DNA molecules and then use DNA ligase to ligate or join them together to create the recombinant DNA molecule, which is going to have the gene of interest connected to the bacterial plasmid.

And so this recombinant DNA can serve as a cloning vector to get the gene of interest into the bacterial cell. In this image, we're showing you an E. coli bacterium, and you can see the bacterial genome right here. And really, this whole video is focusing on this step right here, the second step of DNA cloning which is transformation. The process of this bacterium uptaking external DNA like this cloning vector here. And so through the process of transformation, notice that the cloning vector is going to get into the E. coli bacterium as we see down below right here. And so this E. coli is now an organism that has DNA from a completely different source, a completely different species. It has this gene of interest. And so now this organism is a transgenic organism because it has this recombinant DNA. And so this would be, the transformed E. coli and now it has antibiotic resistance that it has received the gene of interest with the antibiotic resistance.

And so these transformed bacterial cells, they can actually replicate and express the gene of interest, and the researcher can then purify the gene's product and study the gene of interest and the product of the gene of interest. And so, this here is really the conclusion to the second step of DNA cloning which is forming the recombinant DNA into the bacteria. And, we'll be able to get some practice applying these concepts that we've learned as we move forward in our course.