Chapter 9: Biotechnology
Biotechnology,
what is biotechnology, is the use of genetic engineering to produce the desired products and recombinant DNA is DNA that is, that has genes from another organism.
In it, so it's recombined and for example, here you're looking at bacteria that there is they're glowing here is because they are they are carrying genes for a glowing protein that is produced by a specific species of jellyfish, and that's why they're growing. And so the same gene is placed in the plant cell embryo that you can see that is growing as well, as well as this mouse
and the cat, the pig, the you seeing that it's glowing here and even a puppy and even monkeys, animals that carry genes from other organisms in their DNA, they're called transgenic animals. And so this has this technology has a lot of applications very useful to treat diseases. And later, we're going to talk about even treating something like genetic disorders. So a couple of examples here are given to you. For example, this transgenic goat that has the gene for producing human antithrombin, which is a protein that prevents a blood clot formation, and also because it carries a gene in its DNA. This code can produce it produces protein in its milk, which then they isolated, and they can use it for patients that might be susceptible to heart attack. The idea came from observing nature in real life. This bacterium Agrobacterium to tumor patients. It causes Crown Gall disease in plants, which how it does it is that it actually exerts its on this bacterium inserts its own gene, that it's actually carried on its plasmids into the DNA of the plant cell and the what is expressed with other plant genes in the plant. So the plant would produce the tumor
it produces, it induces the plant to put it to make tumor. So this is actually a tumor but is produced because of the bacterial genes that are inserted into the bacteria gene, are coding for anything that is needed to make that tumor. And so it's the bacterium actually lives there and that that's how they're benefiting here. So by observing this site, the scientists thought about ways that this can be used in the new technology, biotechnology and genetic engineering. So also, we know that there are these enzymes that bacteria have. There are different different types of those enzymes together. They're called restriction enzymes that are actually a component of the immune system of bacteria. So they produce these enzymes and there are a few of them mentioned here with the bacteria that produce them. These are produced by the bacteria against viruses because viruses bacteriophage viruses that effect bacteria and the bacteria that can make these restriction enzymes, they actually cut down,
cut the viral DNA and so therefore inactivated. So it's part of the immune system. So the ones that are mentioned, the resolution is are mentioned here. It shows that each each one of those restriction enzymes have the ability to identify certain. Basis in the DNA. And and when it encounters that the those basis, it will cut between, for example, the speed between the ages that go on, whereas this one cuts between one and another. So there are many, many of these restriction enzymes. So they're used as specific tools that that the scientists can use specifically when they know where exactly they want to cut that DNA to get the gene out of that DNA. So here's what is done today, which is using restriction enzymes. They can take the plasmids out of a bacterial cell and then open it, cut it using one of those recission enzymes that they know specifically that is going to be, you know, cut the plasmid at certain points. And then they also cut a DNA of the DNA from another organism using the same restriction enzyme in order to remove the gene of interest from there. And then they insert the gene of interest into the plasmid and then put the plasmid back into the bacteria. And this bacteria, something like that, Agrobacterium Tumor Visions is a bacterium that can't call that can infect plants. So then they would effect a plant. So what happens is that the this is also taken in the gene of interest is also introduced that way into the plant. And so now, as you can see, so whatever that gene was calling for and its product is not, that plant can produce it. So previously you saw the plant glowing dust because that's how they put the gene for the glowing protein from the specific types of jellyfish into the plant cells, and that's where they can grow. So there are different ways of introducing new gene into an organism, for example, in case of bacteria, which they have, which they have said, well, there is another way that they can do this if you remove the bacteria or Savol. And asymmetrically, what's left is called a Proteau plus Socrata plus is a cell without the server. So then they combine these together and what they do, they will fuse automatically, they will fuse together. They actually increase the they can increase the rate of fusion of the two cells by adding polyethylene glycol. That actually increases the rate of fusion. It will be more efficient. So notice that when the two cells fuse, their DNA molecules are also combined. And so now you know what? They have the same genetic information. This bacterium has the same genetic information as the two of them have to begin with. These are protoplasm. And there's also four plants. There is something else that can be used is called Gene Gun. And these are actually.
They shoot tungsten or gold, little gold or tungsten particulates coated with the gene of interest, and then they actually shoot that that gene of interest into a plant cell. And there are machines there, the DNA synthesis machine, they can they can actually insert what they have in the machine. They have all the ingredients that are needed, meaning the nucleotide subunits, the
DNA polymerase is needed to make DNA strand. And all they do is that they program it based on what the sequence of bases are in the gene. And so they already know the sequence of bases for whichever gene it is that they want to make. And the program it and the machine is going to use all the ingredients and put the sequence of bases together, make that gene genes are basically just segments of DNA so they can make it using DNA synthesis into the synthesis machine in case of animal cells, they can actually inject the gene, a new gene into an animal cell. So you here you're looking at an animal under the microscope. So notice that it's held in place at the using this pipette with the suction. So it's held in place that suction. And then here's a little glass
micro pipette with which they're injecting the gene of interest into the nucleus. Actually, they inject it into the nucleus of the cell. Also, bacteria can pick up
DNA fragments and of course, genes when those genes or DNA fragments are in just in a solution or in the media. And that's those would be called naked DNA. So meaning that the cell is disintegrated, DNA fragments are free. The solution, some bacteria can pick those up. And that's called transformation. Some bacteria in nature. They can pick those up naturally, whereas others can be made competent. That capability is called competency. They can be made competent by just using calcium chloride and then and then combine the bacteria with the DNA fragments in a solution and then use a heat shock and add those bacteria. Even if they're naturally not competent, they will be competent and they will pick up dosages. Elixir operation is another way of introducing genes into cells and thus using electric current electric current, which will produce little my pours into the cell membrane through which genes can enter DNA fragments can into. So in biotechnology, they use vectors, vectors or anything that is used in order to deliver the gene of interest into an organism, so vectors can be plasmids, like the examples that I gave you earlier, or they can be viruses. Either way, here you're looking at plasmids that are being used as vectors against restriction. Enzymes are used, specific restriction enzymes are used depending on where the gene is. They know which restriction enzyme to use. And and then once they put that gene into a plasmid, they put it back into the bacterium. And so the bacteria multiplies by binary vision. And so all the progeny will have that recombine. They will have the recombine DNA and therefore the gene of interest would be also expressed. And so all of these bacteria that have the same genetic right genetic material, they're called clones, clones or any cells or organisms that have identical genetic information. That's that's the version of clone. So plasmids can be used to deliver. Genes from one organism to another one. All viruses can be used and here's viruses when they you know, we have viruses that affect plants, those that affect animals and those that effect even bacteria. So they can easily be used to deliver genes. They can remove the virus genes themselves. So what our genes are going in is that they put the gene of interest in there. So it's just the protein coat. And they actually have these libraries that are composed of different viruses or different bacteria where each one of these is carrying a different gene in in its protein coat. And here similarly, these bacteria are which one carries a different gene in its plasmids and they can purchase these depending on which product they want. So this slide is just shows some of the products that we use in medicine, in agriculture, in bioremediation.
And that's they're produced by here. They're showing you what's produced by bacteria. But there are other other organisms that can be used, coli, which is really the microbiology pet
that simply because it's the it's generation time is 20 minutes, meaning that every 20 minutes its population doubles. And so that means they grow quickly. It has just a few genes there. Its genome is has been known for a long time now. And but a decent disadvantage is that it also produces endotoxin. And also another disadvantage is that it doesn't secrete the product is that you have to lice the bacteria open and then collect the product and then purify it and make sure that doesn't have any of the toxin that is produced by the bacteria in it. Yet there are many products that are produced by E. coli and we will talk about some of them, such as this growth hormone, human growth hormone that's produced. It is actually produced by equally simply by inserting the human gene for making human growth hormone into the plasmid of I have equal I produce it and then isolated, purified it used for patients, for children that are born with a deficiency in growth hormone. Insulin is made the same way. Human insulin, saccharomyces servicio, which is a fungus, obviously being a eukaryotic that that has its own advantages in expressing eukaryotic gene a lot easier. That applies to saccharomyces and also plant cells and mammals, all of them being eukaryotic. They have another advantage for expressing their genes and therefore the products that we need. Saccharomyces is also a yeast and it's easy to grow lots of it. And also it has bigger genome, bigger DNA plant cells also or the whole plant. They also, as I mentioned earlier, they expressed that UK has a lot easier. They're also easy to grow at low cost. Mammalian cells are expensive. They're good for expensive Yucatec gene. It's difficult to grow. They can be contaminated easily. They're more expensive to grow, but they're great for producing products that are needed in the in medicine. So I will talk about some of those products here. For example, here, here's the saccharomyces, the yeast I was talking about earlier. I noticed that. Cervical cancer vaccine, which is actually produced by.
Boy, you know it, saccharomyces cerevisiae or insect cells, so animals, those cells are produced by those cells are used as factories in order to make the virus that is protein of the virus that is associated with cervical cancer. And so meaning that they get the gene from the virus, which is papillomavirus, by the way, and they put it in saccharomyces DNA or in insect cells and then have them translate that gene and then make the protein. Then they get the protein from that, and then they use it for treating patients with cervical cancer or using it as a vaccine. I should say and the other one that I like you to know is a ritual protein, which is the hormone that. Promotes bloodsoaked formation. Notice that they're having mammalian cells to produce it, inserting human gene for making this hormone into usually Memet when they say mammalian cell culture, they're talking about. Right. Ovarian cells and have them produce it and purify it. I use it for patients,
interferon, alpha. Is used for leukemia, melanoma, hepatitis, again, you can see by E. coli, saccharomyces beta is for multiple sclerosis and then Gamma is for treating granuloma chronic granulomatous, which we will talk about in one of the chapters that is about immunology. So it just shows you that these products are either used way, as you can see by that yeast we're talking about, or by mammalian mammalian cells. You're looking at insect cells. That's pretty new. Equally that I told you earlier, that is also used as a factory to make human insulin for diabetics growth hormone. The same thing for likelike hepatitis B, vaccine by cerevisiae. Now you need to know these products and what they're used for. You're not required to memorize what exactly what organism is used to make it. But you should know what these products are used for in addition to this one, which I well, if you look at all of them, except this one, the growth factor which is used for the patients epidermal growth factor, not this tiny. All right, so the one that I also want you to know is this one which I forgot to put an arrow. So is all of them, with the exception of epidermal growth factor and some more influence. And I will discuss subunit vaccine shortly. Influenza vaccine. You know, we've we've been vaccinated with flu vaccine that was prepared differently. I don't know, since when they're using it this way, I don't know the one that we're going to be vaccinated with this coming winter or whatever it is that for that we are vaccinated against flu, if that's the way that's going to be used produce. Because traditionally all vaccines, traditionally, they were made either by
if it if they were against bacteria, it would be that bacteria that they were using for those as vaccines against the bacterial diseases. If it were viral, they would use inactivated virus, which would be equivalent to that. Right. We don't we don't use that for viruses because they're not alive, inactivated or weakened. So any of those pathogens could be just weak, not not necessarily dead or inactive. Traditionally, that's those are the vaccines that we've been given. I'm not talking about, by the way, with the exception of covid, which is not a traditional one, but anyway. But influenza vaccine. However, as you can see here, it says that the way they've made it is that they took the gene for a flu virus protein and then put that gene in either E. coli or yeast and have them make that protein. ExpressJet, make the protein. Then they isolate the protein and use that as a vaccine whenever they make a vaccine like that. That's called a subunit vaccine. OK, so which is a lot safer than having a dead bacterium use as vaccine or which bacterium or inactivated virus or which was right. Because it's the whole pathogen that they are giving you in in the vaccine as opposed to this vaccine, which is the protein that they are introducing into your body as a vaccine. All right. So, again, this is the one you know of, obviously, it's a vaccine is a subunit vaccine. Relaxin is again is made by genetic engineering, haven't you? Kolo making it that's used for
is childbirth. But by helping with contractions, less painful contractions. Taxol, which is used for ovarian cancer, again, having Économique it
tissue plasminogen activator for treating blood clots. It's used for heart attack patients, those that have have had multiple heart attacks, tumor necrosis factor to destroy tumor cells for cancer and then also in agriculture, for example. I'm sure you've all heard of Betty Toxi Betty toxin is a bacillus toxin that is bacillus regencies is a toxin that kills, is it? This bacterium actually produces a toxin naturally that kills insects. But what they what they're doing is that they're taking the gene from this bacterium and inserted into corn or cotton or other crops. And and therefore, the plant will will transcribe and translate and make the product of that gene. And the product would be the toxin that kills insects. There are different reasons for genetic manipulation of these organisms, for example, tomatoes and raspberries in order to prevent them from being ripening. And so therefore they increase their shelf life. You might purchaser's those that you purchased and put your refrigerator. They never ripen and they never, never go back. Those are genetically engineered or modified. Simply Roundup also instead of having to use.
Why don't we put the gene in the plants to make their own herbicide? This is a this is
mosquito. Aedes aegypti is a mosquito species of mosquito that transmits Zika virus to people. And so that's a good thing to do. The way that they have that they have manipulated this is that they have released into the environment these male mosquitoes, that
they have a gene that when they produce new mosquitoes, any male mosquitoes that they produce, they are going to die. So this way, you know. Destroying the population of this vector is a vector that transmits disease to people. I'll let you read through this. You're looking at this Hammergren everything else that you eat with it and every single item in it is actually genetically modified. Same day with Starbucks decaffeinated, one is actually modified. And the reason for modification is that the process of the combination is expensive, requires lots of water. Is that it will it will be a lot easier and cheaper to actually remove by inviting analogy, using genetic manipulation, remove the gene that produces Kefi. Cloned meat and any other there are many you can do your own simple research, you can find anything. A list of what's genetically manipulated, a genetically modified food that we are consuming today, which in Europe they actually call them Frankenfood. And the many places in Europe they have they're actually banned. And there are ethical concerns or social concerns. I'll let you read through this if you're interested. How about gene therapy? Gene therapy is could potentially be the only cure for genetic diseases. As you know, genetic diseases, genetic disorders do not have cure you. You can treat the. Symptoms, but you can't cure them. There are about 15 thousands of them, and some of them actually are deadly. So gene therapy is. Is. Again, using. Biotechnology, what if you can remove you can insert a healthy version of the gene into the body of the person who is suffering from a serious genetic disorder or a disease that could potentially be fatal? What if you can fix that? What you can do if you can give the patient the healthy version of that gene so that the healthy products would be made. So
in 1980, some of you might have heard about David Vitter. In the 1980s, he David Vitter was born with one of these genetic diseases. It's called severe combined immune deficiency, where they're born with those babies are born with absolutely no immune system. And so therefore, he had to spend his whole life in sterilized in these sterilized compartments that they made for him.
Away from everybody else and even taking a picture with his mom, he had to still be in this sterilized compartment. So eventually he grew tired of it. He was about 11 years old. And so they decided to give him a bone marrow transplant from his sister about two months after receiving the bone marrow transplant. He actually died of cancer. And so they you know, they couldn't help it. These two.
Kids Ashanti de Silva and Reese events, they were born with the same disease, but later she was born in 1990 and he was born a few years after that. And they used gene therapy for them, for both of them. And it was successful. I don't have the most recent pictures, but this is that baby. And this is Ashanti. This this was this. These pictures are from a few years ago. So they lived to talk about the experience. You can find Ashanti's to talk on the subject. And so what did they do for that gene therapy? And the way they did it was this. They actually used animal words, words that can infect animals they introduced. The gene that is would give the patient person a healthy immune system and used the gene into that virus to remove the water DNA, put that in there and then infected the bone marrow. And some of those bone marrow cells took the gene, some didn't, some to the ones that took the gene, there were enough of them that they they expressed those genes and the they were killed. They started having a healthy immune system. And so there have been other cases where it didn't work there. So they are using this technology. They've had successes. They've also had some cases where the patient died as a result. And so the problem with this is that it's pretty predictable because unpredictable because this gene was introduced, you know, the effect of bone marrow induces into some of these cells. And then where it ends up in that DNA is cannot be predicted using this technology, it cannot be predicted, would actually end up in the DNA. In cases like these two, it worked. But that gene can easily, you know, insert itself anywhere in the DNA, maybe even in the middle of another another important gene where the function where it's going to destroy make that gene not function anymore or can even cause cancer by inserting itself right next to a proton, which then will become oncology. And that's cancer causing. So and also some patients in this case, they had a severe allergic reaction to the protein coat of that, whereas, you know, they removed the viral gene. But the protein could still there is used as a victim of a severe allergic reaction that they would die from it. So, yeah, even though they had some successful cases, but it's unpredictable. And so, of course, now we have something called CRISPR technology, which you might have heard of, and that's thanks to what it actually was, multi, multi multinational effort. Many scientists from different parts of the world who were involved, including Hershey's France, Emmanuelle Charpentier, but Jennifer Doudna of UC Berkeley here, actually, she was heavily involved with this experiment was. It was directed by her here in UC Berkeley. Both of them got the Nobel Prize actually for the 2020 CRISPR technology that you might have heard of it. This is called gene editing was called genetic because using this technology, they they can go they know where exactly, you know, to is. They can actually pinpoint and insert the remove the faulty gene, insert the healthy gene in a specific place. It's not just random. Introduce it in there like previously. And that's the beauty of it. That's why they had the they had they were presented with Nobel Prize. And this is actually in 2016, the first clinical trial trial was actually approved for cancer patients.
They've been successful in repairing a defective gene in Moscow, dystrophy in mice. These are still right. This this is still research. This is the first twenty sixteen was the first actually approved use of use, use of it in clinical setting. I know that there is a company in Boston where my brother actually was. The director and they were using they're using this gene technology, DNA editing to force that anemia.
They were all tried, but they had actually gotten to a point where they would actually try trying them on six or so patients. So it's a very promising technology. You promise? All right. Something else that is new is.
Gene silencing, using what you can make in the lab. Those are called small, interfering RNA. It's a small, interfering RNA. So if you know that the defective genes sequence right of bases, you can make the RNA, these little RNA in the lab that would be complementary to that DNA. And so so they make these the using gene therapy. So they make these in the lab. They already know the code for the, you know, that gene of interest that they want to remove. And so they're going to send this in. And so they are going to, you know, this the DNA with its abnormal gene still going to be transcribed. And once the transcription is out of the nucleus, these lab made smaller tissues. Earnings are going to find the complementary base and bind it and cause it to disintegrate. That's gene silencing. So those genes will never be expressed and the faulty product could not be made. So they have clinical trials for Ebola right now. So I haven't followed it recently to see where he went. But you certainly can.
DNA fingerprinting has been here for a long time, you might have even studied it in your general biology because it's discussed there also, and that relies on the fact that even though about 99 percent of our DNA sequence of bases are all the same in every one, but we all have these short and we have the long repeated basis. There are both short and long repeated bases of this. OK, and so what happens is that the number of these repeated bases is different in everyone. So it's unique to an individual person. They know exactly where they are. I think there are about 13 specific sights along the DNA molecule in everyone that these short repeated segments are found. But their length is different in every one. And those are called those are what they're looking for in DNA fingerprinting, because these are unique to everybody. That's what they're looking for. And using restriction enzymes, they can cut DNA into little fragments. Those fragments are called reflect. And and then that's what they do. They will introduce the DNA fragments into. These little paws that they create in a gel slap, there's a buffer in this container and electricity supply. This is called a gel electrophoresis. That way they could let me first show you this. They can use it in crime scene investigations. They can also establish paternity. They can also run these on use the DNA fingerprint of the microbiome of a person because the microbiome of every person is unique. It's a slightly different from someone else's. So that way they can use these, for example, in cases of sexual abuse cases and then also to find out the source of an infection, for example, or identify a pathogen. So here you are looking at this one. It shows you the source of a food borne disease that food borne the food is a specific apple juice. And they want to know where the patients that have suffered food poisoning. They want to see if it was due to contaminated juice or not. So they have isolated the bacteria from those patients and then from the apple juice and noticed that the DNA fragments must have been of this E. coli versus the apple juice. They're exactly the same size and same length. That's why you see the same pattern in all of these as opposed to these. If you look at these, you see that the pattern is one, two, three, four. The four columns here are not the same as this. So meaning that these patients I mean, these people, they from this from these people were exactly the same as the caller from that apple juice. Nanotechnology is another.
New use of bacteria in order to.
Maybe use a new way of.
Sending a specific medication into the patient, which would target specifically the targeted area. So what they're looking for are these nanoparticles, these so small of metal particles that they can use, maybe they can use its molecular size like a robot to deliver a medicine to specific parts of the body. Or they can also be used to detect food contamination, plant diseases and even the presence of any potential biological weapons anywhere. So they use bacteria to make these nanoparticles. And because there are some bacteria that actually can break down these different
metals, such as gold, silver, selenium, and this one is cadmium in this white selenium where they can break them down into little nano size and then they can use those. So these are produced by bacteria. They're there. They use them in what's called nanotechnology. So here's a potential here's actually a case of application of this nanotechnology already where here's a bacterium that is used in Sweden to make nanofibers for artificial blood vessel. Yep, that's just wonderful. All right, so this chapter just give you a little bit of introduction into the world of biotechnology and some of the things that are available out there. All right. I'll stop here. You guys talk to you later. Bye.
Biotechnology is the use of genetic engineering to produce desired products, with recombinant DNA being DNA that contains genes from another organism.
1. Recombinant DNA Technology
Recombinant DNA involves combining DNA from two different species.
Example: Bacteria carrying a gene for a glowing protein from jellyfish.
These transgenic organisms (like glowing plants or animals) integrate genes from other organisms into their own DNA.
2. Applications of Biotech in Medicine
Transgenic Animals:
Animals modified to express human proteins for therapeutic purposes.
Example: A transgenic goat produces antithrombin, a protein that prevents blood clots. It is found in the goat's milk and can be harvested for medical use.
3. Observing Nature as Inspiration
Agrobacterium tumefaciens:
A bacterium that transfers its DNA into plants, causing tumor-like growths.
This natural mechanism has inspired scientists to use similar techniques for genetic engineering in agriculture.
4. Restriction Enzymes in Genetic Engineering
Enzymes used by bacteria to protect against viral DNA by cutting it.
These enzymes are crucial in biotechnology for cutting DNA at specific sequences to remove or insert genes.
5. Gene Delivery Methods
Plasmid Vectors:
Plasmids can be manipulated to carry genes of interest and introduce them into bacteria or other cells.
Gene Gun:
Introduces genes into plant cells by shooting DNA-coated particles into the cells.
Electroporation:
Uses an electric current to introduce DNA into cells by temporarily permeabilizing the cell membrane.
Transformation:
Some bacteria can take up naked DNA from their environment.
6. Cloning and Vectors
Clones:
Cells or organisms with identical genetic information.
Vectors Can Be Plasmids or Viruses:
Bacteria like E. coli are commonly used as factories to express proteins from human genes, such as insulin.
7. Biotech in Medical Products
Production of Drugs:
Insulin, growth hormones, and vaccines (e.g., cervical cancer vaccine using yeast).
These products are often made in E. coli or yeast due to their rapid growth and ability to express eukaryotic genes.
8. Genetic Modification in Agriculture
Crops are engineered to resist pests or herbicides (e.g., Bt toxin in corn).
Gene technology improves crop yield and longevity by delaying ripening or enhancing resistance to diseases.
9. Ethical Concerns and Food Safety
Genetic modifications are controversial in some regions, raising ethical and health concerns (commonly termed "Frankenfoods").
10. Gene Therapy
A promising approach to cure genetic diseases by inserting healthy genes into patients' cells.
Historical cases include the treatment of severe combined immune deficiency, utilizing viruses as delivery systems to introduce healthy genes to patient cells.
11. Current Trends: CRISPR Technology
A breakthrough in gene editing allows precise modification of DNA sequences.
This technology has advanced gene therapy and potential treatments for genetic disorders with improved safety.
12. DNA Fingerprinting
Used in forensic science and paternity testing by analyzing unique patterns in DNA sequences among individuals.
13. Nanotechnology in Biotechnology
Use of nanoparticles for targeted drug delivery, food safety, and environmental monitoring.
Bacteria can be engineered to produce these nanoparticles for various applications.
Biotechnology holds immense potential in medicine, agriculture, and beyond, improving health outcomes, food security, and environmental sustainability. As technology advances, ongoing ethical discussions are critical to ensure safe and responsible applications.