Biochemistry in Perspective 101: Applications of Biochemistry in Daily Life

Foreword

Biological organisms, such as humans and their individual cells, are incredibly complex and diverse systems. Nevertheless, certain unifying characteristics exist in all living things, from the simplest bacterium to the human being. The same types of biomolecules are present and they all use energy to function. These molecules are known as proteins, lipids, glycans, and nucleic acids. From the construction, modification, and interaction of these components, our cells develop and carry out specific functions. Biochemistry draws on a wide range of scientific disciplines to explore and study these molecules, cells, and functions. This has sequentially allowed us to gain a better understanding of the human body at the molecular level, which has led to more effective treatments in medicine. We will explore biochemistry in the context of this series, which examines the role it has played and will continue to play in our daily lives. In a nutshell, all life is the embodiment of biochemistry, and everything a living organism does is an expression of a biochemical process.

This 101 series is divided into six articles, including:

1. Biochemistry in Perspective 101: Amplifying Biochemistry Concepts

2. Biochemistry in Perspective 101: Biochemistry of Metabolism in Health and Disease

3. Biochemistry in Perspective 101: Applications of Biochemistry in Daily Life

4. Biochemistry in Perspective 101: Natural Biochemical Cycles

5. Biochemistry in Perspective 101: Biochemistry and its Applications in Drug Development

6. Biochemistry in Perspective 101: Advances and Prospects in Biochemical Research

Biochemistry in Perspective 101: Applications of Biochemistry in Daily Life

Most notably, biochemistry had a significant impact on the medical and pharmaceutical fields. Biochemistry is, however, also essential to everyday life, affecting everything from retail to food, from cosmetics and fashion to healthcare [Figure 1].

Many products and processes in our daily lives are enabled by our expanding understanding of biochemistry. Among them are the development of medical products and cleaning products, as well as DNA recombinant technology, which serves the purpose of producing important molecules like insulin and food additives (Campbell et al., 2016).

Figure 1: Biochemistry applications in every day life.

Moreover, biochemical research has contributed greatly to the improvement of food quality and security by developing improved agrochemicals, creating crops that are more resistant to pests and diseases, and preparing foods that promote human health, such as prebiotics and probiotics. These agrochemicals include fertilizers, plant protection chemicals and plant growth stimulators used in agriculture. This article will focus on the role biochemistry plays in various aspects of our day-to-day lives.

Biochemistry in Medicine and Healthcare

It is essential to understand the relation biochemistry has to health and disease for it has been crucial in discovering various diseases as well as in developing treatments. Usually, a biochemical analysis of blood and enzymes is used to detect and monitor diseases. It facilitates the development of pharmaceuticals, vaccines, and diagnostic tests. Among the elements that have been very useful in developing treatments and diagnostics are enzymes. Enzymes are not only proteins that assist in speeding up reactions within the body, but they are also essential in treating disorders. In some disorders like low blood pressure, and head and spinal injuries, there are chances of blood clot formation, which means that the blood flow in a vein is obstructed. For organs that require a constant supply of oxygen, such as the brain and heart, a blood clot can be life-threatening. These clots are usually removed through dissolving, by means of enzymes that can break them down. In the case of wound healing, swelling may cause pain and pus formation. It is common to use enzymes like trypsin, serratiopeptidase and chymotrypsin to dissolve swellings. Patients suffering from indigestion may be given gastrointestinal tract enzymes such as pepsin, trypsin, and lipase to treat gastrointestinal diseases. The enzyme asparaginase is used as an anticancer drug (Babbal et al., 2019). In addition to using enzymes to treat diseases, they are also used to make diagnosis and prognosis. The most common HIV test uses blood to detect an HIV infection, which is called an enzyme-linked immunosorbent assay [ELISA, Figure 2] to test a patient’s blood. Furthermore, immobilized enzymes like glucose oxidase (GOD) and peroxidase (POD) are used for the measurement of blood glucose. Serum enzymes are used as markers to detect cellular damage which in turn helps with the diagnosis of diseases (Meghwanshi et al., 2020).

Figure 2: ELISA test assay to detect HIV infection (Helvetic health care, 2020).

Biochemistry in Gene Cloning and Genetic Engineering

Genetic engineering is the process of altering the genetic material or cells of living organisms in an attempt for those cells to create new compounds or produce new functions. The technology and methodology behind genetic engineering have been used throughout the history of agriculture, to improve livestock and crops through selective breeding. Genetic engineering is also referred to as recombinant DNA (rDNA) technology, which is defined as the manipulation and transfer of genes from one organism to another to create novel DNA. The term recombinant is used because DNA from two different sources can be joined together.

Despite discovering DNA's structure in 1953, scientists did not possess the ability to make recombinant DNA until two decades later. Leading up to the discovery of rDNA technology, scientists discovered that plasmids, which are small mobile pieces of DNA, are able to replicate in huge quantities and that they could transfer genetic information. It was this process that gave host bacteria the capacity to inherit new genes and therefore new functions, such as resistance to antibiotics. Furthermore, in the 1960s, American biochemist Stuart Linn and Swiss microbiologist Werner Arber [Figure 3], discovered that bacteria have a defense mechanism against attacking viruses (Bose & Bose, 2022; Loenen et al., 2014). Bacteria could protect themselves by producing endonucleases, otherwise known as "restriction enzymes". These enzymes could seek out a single DNA sequence in the virus and cut it off precisely in one place, preventing the replication of the virus which then prevents the death of the infected bacteria. In 1968, Harvard University researchers Matthew Meselson and Robert Yuan isolated and purified Escherichia coli K, the first restriction enzyme (Loenen et al., 2014). The first site-specific restriction enzyme, HindII, was isolated and characterized two years later by Hamilton Smith [Figure 3], Thomas Kelly and Kent Welcox at Johns Hopkins University. Daniel Nathans [Figure 3] demonstrated this to be a useful tool for cutting and pasting specific DNA segments. Shortly after, Peter Lobban and Armin Dale Kaiser from Stanford University created the first protocol for producing recombinant DNA. Paul Berg, a Stanford University scholar, demonstrated the feasibility of cutting and pasting genes. Two years later, Stanley Cohen and Herbert Boyer combined their efforts to successfully insert recombinant DNA into bacteria for replication (Berg & Mertz, 2010; Vettel, 2004).

Figure 3: Werner Arber, Daniel Nathans, and Hamilton Smith were awarded the Nobel Prize in Medicine/Physiology in 1978 (Nobelprize, n.d.).

Cloning, on the other hand, refers to the creation of the perfect replica, and, in general, it is used to describe the creation of genetically identical copies. The process of reproducing a whole organism is called reproductive cloning. Prior to the creation of reproductive clones, researchers learned how to copy short DNA segments, a process called molecular cloning. The most well-known example in the history of genetic cloning is Dolly, a female Finn Dorset sheep that lived from 1996 to 2003, she was the first clone of an adult mammal, produced by British developmental biologist Ian Wilmut [Figure 4] and colleagues of the Roslin Institute, near Edinburgh, Scotland (García-Sancho, 2015). During gene cloning, a piece of DNA fragment is inserted into a bacterial cell where DNA is multiplied or copied as the cell divides.

The basic steps involved in gene cloning are:

1. Isolation of desired DNA fragment by using restriction enzymes

2. Insertion of the DNA fragment into a suitable vector, like plasmid, to make recombinant DNA

3. Transfer of rDNA into bacterial host cell, transformation

4. Selection and multiplication of recombinant host cell to get a clone

5. Expression of cloned gene in the host cell.

Using these strategies, several enzymes, hormones, and vaccines can be produced. One of its earliest applications in the pharmaceutical industry was the use of gene-splicing technology to produce insulin.

Figure 4: Dolly the sheep with biologist Ian Wilmut (The Roslin Institute, n.d.).

Instances Observed in Agriculture

Genetic engineering and recombinant DNA technology have not only played a big role in advancing medicine, but they have also led to significant advancements in the agriculture industry. These advancements brought about the development of genetically modified crops, improving agricultural productivity and disease resistance (Colwell et al., 1985; Paoletti & Pimentel, 1996).

Genetic engineering in plants appears to cause less controversy in comparison to its application in mammals, but many people still have concerns about it. It is important to realize that many of the modifications made using genetic engineering are simply controlled versions of the selective breeding that has been used for centuries to improve crop and animal production. In spite of this, many types of modifications have been made, and in some instances shown success. Herein are listed several examples:

Disease Resistance

Specialized strains which are mainly used in high-yielding crops are more susceptible to fungal disease and insects. Due to this, it is necessary to use a significant amount of insecticides and herbicides during the growing season. Often, other plants have a natural resistance to these diseases and pests. This has led scientists to try to isolate and transfer these specific genes that cause the resistance, into other plants, although with limited success. News surrounding Bt corn, sparked many controversies and public concern surrounding genetically modified foods and crops [Figure 5]. Bt corn is a crop that contains a special bacterial gene that produces a toxin, poisonous to caterpillars. In order to increase crop yield, the Bt gene is extracted from the donor organism and transferred to corn and cotton (Abbas, 2018). In turn, this results in fewer insecticides being used during crop production. However, this poisonous toxin can also cause potential harm to other species: for example, it has been shown through lab tests that planting Bt corn would have the same effects on monarch butterflies as it does on caterpillars.

Figure 5: Bacillus thuringensis corn (Bt corn) (Blueberries consulting & AAS, n.d.).

Frost-free Plants

Some organisms such as plants, fungi, bacteria and animals -e.g., fish from the Antarctic- produce proteins called antifreeze or ice structuring proteins (Jia & Davies, 2002). These proteins, such as the one depicted in Figure 6, have hydrophobic surfaces that permit the survival of these organisms in temperatures below the freezing point of water. Frost damage is caused by exposure to freezing temperatures. A drop in temperature causes the water in plants, crops, and other materials to freeze and expand, causing the rupture of the cells. This led scientists to insert the gene for the antifreeze protein into crops such as strawberries and potatoes specifically in areas with very short growing season. There has been much controversy over these crops since, in each case, a foreign gene was introduced from a non-plant species to a plant species. There is widespread concern about cross-species gene modification, even though the modified product's taste and texture are indistinguishable from those produced by unmodified plants.

Figure 6: Structure of Choristoneura fumiferana (spruce budworm) beta helical antifreeze protein (Wikipedia, 2009).

Tomatoes with a Long Shelf Life

The first commercially grown genetically engineered food to be licensed for human consumption was the Flavr Savr tomato (Redenbaugh, 1992). The plant has been genetically modified, but no new gene has been introduced; instead, one of its own genes has been disabled. The gene in question allows the plant to produce ethylene. Ethylene is a chemical compound that is released during the ripening process of the fruit. In the absence of this gene, the tomatoes mature on the plant until they just begin to show pink color, the exact stage at which tomatoes are picked and sent to market. Usually, unmodified tomatoes will be picked up as many times as nine in one season, mainly because they all ripen at different rates. It is common for these tomatoes to continue producing ethylene, resulting in overripening, softening, and deteriorating over time. The modified tomatoes can be harvested once or twice, and their fruits can be made to ripen using exogenous ethylene gas when needed. The shelf life of the Flavr Savr tomato is increased because it does not make its own ethylene, leading to cost and time savings, making it possible to deliver a better and cheaper product on the market. The taste of the modified tomatoes is indistinguishable from the unmodified unmodified ones.

Increased Milk Production

Bovine somatotropin (BST), also known as growth hormone is a natural protein hormone that regulates milk production in cows. This hormone increases metabolism and milk volume in dairy cows. There is much controversy surrounding the consumption of the hormone by humans. As a peptide hormone, BST is hydrolyzed in the digestive tract and not absorbed directly into the bloodstream. Furthermore, cows cannot produce milk without this hormone, so all milk contains it (Barbano et al., 1989; Mlynch, 1989). However, BST cows are more likely to develop mastitis, inflammation and infection of the teats of the udder [Figure 7]. This is due to the fact that the higher-producing cows are milked, and therefore handled more often. Often, although milk is strictly tested for the presence of antibiotics, when treating mastitis, antibiotics may nevertheless end up in the milk, causing food sensitivity in some people.

Figure 7: Mammary infections in BST treated cows require treatment with antibiotics (Biology Weebly, n.d.).

Biochemistry in Nutrition

Recent years have seen a growing interest in the impact of nutrition on both physical and mental health. More and more studies are finding strong connections between diet, gut health and the microbiome, as well as various diseases. The field of nutritional biochemistry centers around investigating the mechanisms underpinning these interactions between diet and diseases. As part of the biochemistry of nutrition, a variety of scientific disciplines, including biology, chemistry and physics, are employed to gain a deeper understanding of topics such as cell function, metabolism, nutritional genomics, macronutrients, energy and other factors that influence diet and disease interactions. Researchers in nutritional biochemistry aim to determine the optimal dietary and nutritional requirements of healthy and ill individuals. Moreover, the field aims to reduce the side effects of pharmaceuticals. A few examples of the importance and the impact that diet and nutrition have on our health are listed below.

A Green Diet

According to recent research, the Mediterranean diet is associated with better overall mental and physical health than Western diets, often associated with unhealthy eating patterns. Recent evidence also suggests that the green Mediterranean diet is more strongly associated with better mental health than the classical Mediterranean diet. This diet is rich in all of the important daily minerals and vitamins needed for our health. One of these vitamins is folic acid [Figure 8]. In the United States, folic acid deficiency is probably the most common vitamin deficiency, especially among pregnant women and alcoholics. A deficiency in folic acid can lead to anemia, a condition in which the blood has lower-than-normal concentrations of hemoglobin. This results in a reduced ability of the blood cells to transport oxygen. There are two types of nutritional anemia. The most common form is microcytic anemia, where the size of the RBC is below normal, usually due to deficiencies noted in a person's diet such as the lack of iron. A deficiency of folic acid, or vitamin B12, causes macrocytic nutritional anemia, where the RBC size is above normal (Herbert, 1965; Lucock, 2004). A folate-free diet can cause a deficiency within a few weeks.

Figure 8: Foods that are rich in folic acid (Canva, n.d.).

Healthy Cells and Tissues

Nutritional biochemistry has provided insight into how nutrients influence the growth, development, and function of cells and tissues as well. Several studies have shown the importance of nutrients in the metabolic system and in maintaining cellular homeostasis. The latter is referred to as the processes involved in maintaining the internal steady state of cells (Ma et al., 2022). Some studies have shown that external stress responses can affect the internal homeostasis of a cell, which can lead to triggering the onset of diseases. Therefore it is important to maintain metabolic nutrition for our cells and tissues.

Diet and Cancer

A great deal of evidence has been generated by nutritional biochemistry regarding the role of diet in the development of cancer. Until now, genetics has been viewed as one of the most important influences in cancer development. Moreover, genetic factors, such as DNA instability and gene alterations, have been shown to be influenced by nutrition and diet. Furthermore, nutrition may also influence aberrant DNA methylation, a key contributor to carcinogenesis. Nutritional experts suggest adding foods that contain phytochemicals, also known as phytonutrients, to a person's. These compounds are known to help prevent chronic diseases such as cancer. The list of foods containing phytochemicals includes; berries, broccoli, tomatoes, walnuts, grapes and other fruits, vegetables and nuts. More than 4,000 different types of phytochemicals have been discovered and researched, and a few can be seen in Figure 9 below, where their different functions and benefits are detailed (Donaldson, 2004).

Figure 9: Various phytochemicals present in food.

Biochemistry in Cleaning Products

Detergents

Detergents are synthetically derived compounds, i.e. sulfates and sulphonic acids which are derived from petroleum, dyes, perfumes, phosphates and many more substrates. They also generally contain different types of biodegradable enzymes such as proteases, amylases, lipase, cellulases, mannanases, and pectinases. The action of enzymes in detergents helps break down stains and organic materials, making the cleaning process more effective. To improve stain-fighting performance, different enzyme types have been combined. The advantage of detergents over soap is that they can be used with hard water as well as in acidic conditions. A wide range of enzyme products are available as liquid formulations with stabilization systems for liquid detergents as well as encapsulated granules for powder detergents and soap bars.

Soaps

Chemically, soaps are fatty acid salts since they are composed of an ionic head and a nonpolar glyceride tail. Soaps are made from animal fats or vegetable oils. These products contain glyceryl esters o long-chain fatty acids also known as glycerides. They consist of one, two, or three fatty acids esterified on glycerol, and hence are referred to as mono-, di-, and triglycerides, respectively. As glycerides are heated with sodium hydroxide, soap and glycerol are produced. Salt is added to the reaction mixture to decrease the soap's solubility and precipitate it out of the aqueous solution. Colors, perfumes, and chemicals of medicinal significance are then mixed into the soap. Its quality is described in terms of total fatter matter (TFM). TFM is defined as the total amount of fatty matter that can be separated from a sample after it has been split with mineral acids. The greater the amount of TFM in the soap, the better the quality. To understand how soap works we can consider sodium palmitate [Figure 10], the carboxylate ion shown in its structure is directly responsible for soap's cleansing action. The structure of palmitate is both polar and non-polar exhibiting dual polarity. The hydrocarbon chain is non-polar and considered hydrophobic while the carboxylic portion of palmitate is polar and considered to be hydrophilic.

Figure 10: Soap and the structure of palmitic acid (Canva, n.d.).

The hydrophobic portion is soluble in oils and greases, but not in water unlike the hydrophilic carboxylate group, which is soluble in water. Dirt particles present in materials and clothes are due to dust, grease, fats and oils. As soon as the soap is applied to an oily or greasy part of the material, its hydrocarbon part dissolves in the oil or grease, leaving the the negatively charged carboxylate end of the palmitate exposed and free. Additionally, the negatively charged carboxylate groups in grease are strongly attracted by water, causing small droplets called micelles to form and grease to float away. When the water is rinsed away, the grease goes with it. Resulting in material free from dirt particles (Campbell et al., 2016).

Application of Biochemistry in Forensics

DNA is unique to each individual. When reproductive cells develop and fertilize, sets of individual chromosomes are transmitted to the offspring in so many different combinations that there is no way for any two individuals to share the same DNA. The exception to this rule is identical twins, which occurs when the egg divides after fertilization has occurred.

In cases involving the issue of identity, DNA tests alone, without supporting evidence, have sometimes been sufficient for convictions. Today, DNA evidence almost always suffices for exonerating wrongly convicted individuals. There are many body tissues or fluids that contain DNA that can be used as DNA evidence. When determining if DNA from the scene of a crime matches the suspect's or victim's DNA, two major types of testing are used. One technique is known as DNA fingerprinting [Figure 11] and the other is polymer chain reaction (PCR) amplification followed by hybridization or sequencing. The evidence gathered from crime scenes can be compared with tissue samples taken from suspects.

Figure 11: DNA fingerprinting (National Human Genome Research Institute, n.d.).

DNA Fingerprinting

There are small differences between each person's base pairs, which makes their DNA sequence unique. For this reason, DNA fingerprinting is the faster and more straightforward method for comparing genetic differences between two individuals. Alec Jeffrey developed this technique in 1984 at the University of Leicester's Genetics Department (Kirby, 1993). DNA fingerprinting is widely used in forensic crime investigations, to identify culprits or accessories to crimes. It is also used for paternity testing in cases of dispute. DNA fingerprinting is also used to study the genetic diversity of populations, evolution and speciation [Figure 12]. Using this technique, each individual's DNA sequence can be analyzed and its distinctive characteristics can be identified. A variable number of tandem repeats (VNTRs) can be used as a molecular marker to identify a sample.

Approximately 99% of DNA bases in humans have the same sequence. This is referred to as bulk genomic DNA. The remaining 1% DNA sequence differs from one individual to another. This 1% is composed of repeated sequences that are known as satellite DNA. DNA segment sizes vary depending on the number of repeats, also called VNTRs, in an individual.

Figure 12: DNA fingerprinting illustration (Canva, n.d.).

Polymerase Chain Reaction (PCR)

Scientists use polymerase chain reaction (PCR) to make millions to billions of copies of a specific DNA sample quickly, enabling them to study a very small sample of DNA in detail. This method was invented by American biochemist Kary Mullis in 1983. In 1993, Kary Mullis and Michael Smith received the Nobel Prize in Chemistry for their joint efforts in their work on manipulating DNA (Bartlett & Stirling, 2003). Many genetic tests and research procedures rely on PCR, including analyzing ancient DNA samples and identifying infectious agents. The PCR process involves exponentially amplifying small amounts of DNA sequences in a series of temperature changes. There are now numerous applications for PCR in medical laboratories, including biomedical research and criminal forensics.

Conclusion

Biochemistry has numerous applications in daily life, encompassing areas such as medicine, healthcare, nutrition, agriculture, biotechnology, energy production, and more. Biochemistry plays a crucial role in advancing scientific knowledge, improving human health and enhancing our understanding of the natural world. The study of biochemistry has contributed to the development of lifesaving drugs and diagnostic tools by providing insight into the molecular basis of diseases. In nutrition, biochemistry contributes to dietary recommendations and ensures food safety and quality through an improved understanding of biochemical pathways involved in nutrient metabolism. Using biochemistry in biotechnology and agriculture has facilitated genetic engineering and the creation of genetically modified organisms, which have enhanced crop yields and disease resistance. Furthermore, biochemistry plays a crucial role in everyday products, including household cleaners, cosmetics and skin care products.

Biochemistry continues to drive innovation, shaping various industries, and improving our daily lives. As our understanding of biochemistry advances, we can expect even more profound applications that will further benefit humanity and the world we live in.

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