Information

Is this bacteria or fungi?


I've been growing bacteria on an agar plate and after putting the dishes in the incubator, this is what I saw. I'm new to bacteria identification, and is this just contamination by fungi or is this actually bacteria colonies? I suppose it is fungi, but what about the white, round white circles on top of the fungi(the top, left picture), is that bacteria colonies?


It's probably mostly fungal contamination if you did not sterilize and left the container open. This video on how to isolate bacteria better may help: https://www.jove.com/video/3064/aseptic-laboratory-techniques-plating-methods

Good luck!


Food Poisoning Caused by Bacteria and Fungi

In this article we will discuss about the food poisoning that is caused by bacteria and fungi.

Food-Poisoning Caused by Bacteria (Bacterial Food-Intoxications):

There are two major food-poisoning or food-intoxications caused by bacteria.

Botulism and Staphylococcal-poisoning.

1. Botulism:

Botulism is caused by the ingestion of food containing the neurotoxin (toxin that affects the nervous system) produced by Clostridium botulinum, an anaerobic spore forming bacterium. Sixty to seventy per cent cases of botulism die. There are 7 types (type A, B, C, D, E, F, G) of these neurotoxins recognised on the basis of serological specificity.

The neurotoxin of C. botulinum is a protein. It has been purified and crystallized and is so powerful that only a dose as low as 0.01 mg is said to be fatal to human beings. The toxin is absorbed mostly in the small intestine and paralyzes the involuntary muscles of the body.

The main sources of botulism are canned meat, fish, string beans, sweet corn, beans, and other low medium acid foods. The foods implicated are generally those of a type that have undergone some treatment intended for the preservation of the product such as canning, pickling or smoking, but one which failed to destroy the spores of this bacterium.

When the intended preservative treatment is inadequate and is followed by storage conditions which permit the germination and growth of the microorganisms, one of the most lethal toxins known to humanity is produced. The toxin has been known to persist in foods for long periods, especially when storage has been at low temperatures. It is unstable at pH value above 6.8.

Temperature is considered to be the most important factor in determining whether toxin production will take place and what the rate of production will be. Various strains of C. botulinum types A and B vary in their temperature requirements a few strains grow at 10 to 11°C. However, the lowest temperature for germination of spores of the most of the strains is 15°C and maximum of 48°C.

Symptoms generally occur within 12 to 36 hours after consumption of the spoiled food. Early symptoms are digestive disturbances followed by nausea, vomiting, diarrhoea together with dizziness and headache. Double vision may occur early and there may be difficulty in speaking.

Mouth may become dry, throat constricted, tongue may get swollen and coated. Involuntary muscles become paralysed and paralysis spreads to the respiratory system and to the heart. Death normally results from respiratory failure.

Canned food should be properly processed by using approved heat processes. Food that has been cooked but not well heated should be avoided. Raw foods and frozen foods thawed and held at room temperature should be avoided. Gassy and spoiled canned foods should be rejected. Boiling of suspected food for at least 15 minutes is required.

Successful treatment is by the administration of polyvalent antitoxin in the early stages of infection. Once the symptoms appear the treatment fails to prove useful.

2. Staphylococcal-Poisoning:

This is the most common type of food-poisoning caused due to the food contaminated with a potent toxin, namely, enterotoxin. This toxin is produced by certain strains of Staphylococcus aureus. A sudden onset of illness starts usually within 3 to 6 hours after ingestion of the contaminated food.

These bacteria are commonly present on the skin, nose and other parts of human body. People who handle foods carelessly usually transfer them to the food. Foods most commonly contaminated involve those which are eaten cold, e.g., cold meat, poultry, salads, bakery products, etc.

As said earlier, the disease starts within 3 to 6 hours after ingestion of the contaminated food and is manifested by nausea, vomiting, abdominal pain and diarrhoea within 24 to 48 hours. If the case becomes severe, dehydration and collapse may follow. However, in usual conditions death is rare.

The disease can be controlled by preventing the entry of the bacteria to food. It is important that all susceptible foods are kept under refrigeration to restrict the growth of the bacteria and also by the destruction of the bacteria by heat.

Food-Poisoning (Mycointoxications) Caused by Fungi:

Mycotoxins are chemical substances produced by a variety of fungi, e.g., aspergilli, penicilli, Rhizopus, Fusarium spp., and mushrooms (poisonous called toadstools). The illness that results from the ingestion of foods containing fungal toxins is called ‘mycotoxicosis’. Mycologists have come to discover a number of mycotoxins which have proved extremely harmful, sometimes lethal to animals and human beings.

Important ones are as follows:

1. Anatoxins:

Aflatoxins are one of the most potent mycotoxins produced by Aspergillus flavus and related strains. It has been found that about 60% strains of A. flavus produce this toxin. This discovery of aflatoxins is comparatively of recent origin. In 1960, about 100,000 Turkey poults died in England within few months. It was found that the peanut meal fed to them was heavily contaminated with A. flavus.

The chemical substance isolated from such peanut meal was found toxic and was named ‘aflatoxin’. However, some other fungi, e.g., Aspergillus niger, A. oryzae, A. ochraceus, Penicillium citrinum, etc. have also been reported to produce anatoxins. So the name aflatoxin is now generally used for a number of related toxins.

Anatoxins occupy the most important position among mycotoxins because of their potent carcinogenic nature and high frequency of occurrence in nature. More specifically, aflatoxin B1 is one of the most potent aflatoxins. They are responsible for liver cancer in laboratory animals and even human beings.

2. Amatoxins and Phallotoxins:

These two mycotoxins are considered to be produced by the poisonous mushroom Amanita phalloides, the so called death cap. This mushroom is deadly poisonous and almost about 90 to 95% deaths of mushroom-eaters in Europe have been due to eating of this fungus. These two mycotoxins are chemically cyclopeptides.

According to Lincoff and Mitchel (1977) the most potent amatoxins are α-amanitin and β-amanitin while the phalloidin is the most potent phallotoxin. However, studies reveal the fact that these are the amatoxins which are strongly poisonous comparatively, and are responsible for producing hypoglycemia, liver-distrophy and kidney-failure leading to the death of the victim.

3. Coprine:

This mycotoxin is thought to be present in an edible mushroom, namely, Coprinus atramentanius. This chemical becomes toxic and results in gastrointestinal upsets and other physical discomforts when the mushroom-eating is accompanied with alcohol.

4. Gyromitrin:

Gyromitrin (monomethylhydrazine) is deadly poisonous mycotoxin reported to be present in the fruiting bodies (basidiomata) of saddle fungi (Helvella spp.) and false morels (Gyromitra spp.). This toxin is water soluble. It is thought that if the fruiting bodies be parboiled two or three times and the liquid discarded, the mushrooms become safe to eat.

5. Ochratoxins:

Ochratoxin was first isolated from the filtrates of Aspergillus ochraceus and is now produced by a number of Aspergillus and Penicillium spp., with Penicillium verrucosum being the dominating producer.

These mycotoxins represent a group of closely related derivatives of isocoumarin linked to L-phenylalanine, an amino acid, and are reported mainly in temperate area of North America and Europe. Ochratoxins occur mainly in grains but have also been reported in coffee, beans and peanuts, and are toxic to ducklings, chicks and rats.

6. Trichothecenes:

Trichothecenes are produced by the species of Fusarium, Cephalosporium, Myrothecium, Trichoderma and Stachybotrys. Out of 30 known trichothecenes, T-2 toxin, nivalenol and deoxynivalenol are of common occurrence, and cause a hyperestrogenic syndrome, haemorrhage and sometimes abortion in swine.


Is this bacteria or fungi? - Biology

  1. ? They are used to make yoghurt.
  2. ? They are used in the manufacture of cheese.
  3. ? They are used in making antibiotics.
  4. ? They can act as decomposers.

Milk, if left out of the refrigerator will quickly go sour.
Which one of the following statements is incorrect?
  1. ? Viruses cause milk to go sour faster.
  2. ? The higher the temperature, the faster the milk will go sour.
  3. ? Bacterial action causes the milk to go sour.
  4. ? As milk goes sour, it becomes more acidic.

Bacteria is grown in the laboratory in petri dishes.
In addition to agar, moisture and warmth, what else is needed to grow the bacteria?

Farmers produce silage to feed their cattle.
To make silage, grass is broken down by

When growing fungi in a petri dish, which one of the following is used to feed the fungi? Which one of the following statements is incorrect?
  1. ? Bacteria cannot respire.
  2. ? Bacteria in soil causes dead plants and animals to decompose.
  3. ? Meningitis and appendicitis are caused by human bacteria.
  4. ? Cheese can be made using bacteria.
Which one of the following species is the smallest?
  1. ? All viruses are parasites.
  2. ? Bacteria are much smaller than a virus.
  3. ? Antibiotics are made from viruses.
  4. ? Viruses can reproduce anywhere.
Tooth decay is caused by sugars.
What feeds on sugars in the mouth to cause tooth decay? In 1796, Edward Jenner discovered vaccines. What did this vaccination cure?
  1. ? Antibiotics produced by white blood cells
  2. ? Bacteria
  3. ? Fungi
  4. ? Any microorganism
  1. ? bacteria and fungi in the soil.
  2. ? bacteria only in the soil.
  3. ? Viruses in the soil.
  4. ? Fungi and viruses in the soil.
Which one of the following statements about viruses is FALSE?
  1. ? Viruses can grow anywhere.
  2. ? Viruses cannot grow in agar.
  3. ? Viruses do not grow but reproduce inside the host cell.
  4. ? Chickenpox and measles are examples of viruses.
  1. ? Antibiotics function by killing viruses.
  2. ? Antibiotics prevent bacterial infection.
  3. ? White blood cells fight infection by producing antibodies.
  4. ? AIDS is a condition caused by HIV (human immunodeficiency virus)

Chemicals produced by bacteria and fungi, and which treat infections caused by bacteria, are known as
  1. ? Fungi contain chlorophyll.
  2. ? Fungi cannot make their own food.
  3. ? Fungi can act as parasites.
  4. ? Fungi can act as decomposers.
  1. ? fungi and bacteria.
  2. ? fungi and viruses.
  3. ? viruses only.
  4. ? bacteria only.

Agar is placed in a petri dish and some soil is sprinkled on the agar. The lid is placed on the petri dish, and it is incubated for two days. After two days, areas of bacteria and fungi are visible on the agar.
What is the name for these areas?

Bacteria, fungi and viruses are also called microbes. Vaccines help our body to fight microbes.
Which one of the following statements about vaccines is NOT correct?
  1. ? Vaccines treat the illness caused by microbes.
  2. ? Vaccines prevent diseases from occurring.
  3. ? Vaccines are usually made from a harmless version of the microbe it is trying to prevent.
  4. ? Vaccines were discovered by Edward Jenner.

Antibiotics are made from fungi.
Which one of the following statements about antibiotics is NOT correct?
  1. ? Antibiotics cannot kill bacteria.
  2. ? Antibiotics are not used to treat the flu.
  3. ? Antibiotics cannot harm viruses.
  4. ? Alexander Fleming discovered the first antibiotic, penicillin.

The image shown was produced using a scanning electron microscope. It shows the bacteria Escherichia Coli.
Which one of the following is a beneficial effect of bacteria?
  1. ? It produces yoghurt.
  2. ? It causes pneumonia.
  3. ? It produces beer.
  4. ? It is used to make antibiotics.

The image shown was produced using a scanning electron microscope. It shows the bacteria Escherichia Coli.
Which one of the following is a harmful effect of bacteria?
  1. ? It causes meningitis.
  2. ? It produces silage.
  3. ? It causes food spoiling.
  4. ? It causes chickenpox.
  1. ? A drug that kills bacteria.
  2. ? A chemical made by white blood cells.
  3. ? A scab formed on cuts in the skin.
  4. ? A drug that attacks viruses.
  1. ? All fungi are microscopic.
  2. ? Most fungi reproduce by producing tiny spores.
  3. ? Some fungi are parasites of plants.
  4. ? Most fungi are made of masses of very long, thread-like cells.
  1. ?
  2. ?
  3. ?
  4. ?

Difference between Bacteria and Fungi

Bacteria occur almost everywhere. They also live in extreme habitats such as hot springs, deserts, snow and deep oceans where very few other life forms can survive. Many of them live in or on other organisms as parasites.

Bacteria are grouped under four categories based on their shape: the spherical Coccus (pi. cocci), the rod-shaped Bacillus (pi. bacilli), the comma- shaped Vibrium (pI: vibrio) and the spiral Spirillum (pI: spirilla) as shown in Figure 11.1.

Though the bacterial structure is very simple, they are very complex in behavior. Compared to many other organisms, bacteria as a group show the most extensive metabolic diversity. Some of the bacteria are autotrophic, i.e., they synthesize their own food from inorganic substrates.

They may be photosynthetic autotrophic or chemosynthetic autotrophic. The vast majority of bacteria are heterotrophs, i.e., they do not synthesize their own food but depend on other organisms or on dead organic matter for food.

Bacteria belong to Kingdom Monera, together with Cyanobacteria (blue-green algae), which are also prokaryotic. Bacteria may be classified based on their shape: spherical (cocci), rod-like (bacilli), spiral (spirochetes), or comma-shaped (vibrios). Other ways of classifying them are based on whether or not they are: gram positive or gram negative, aerobic or anaerobic, autotrophic or heterotrophic, etc.

Fungi:

The fungi mabes bread develops a mould because of fungi. The common mushroom and toadstools are also fungi. White spots seen on mustard leaves are due to a parasitic fungus. Some fungi are used to make bread and beer. Some fungi cause diseases in plants and animals. Some fungi are the source of antibiotics, such as Penicillium. Fungi exist in air, water, soil and on animals and plants.

Various types fungi are shown in colored image 11.1. Fungi bodies consist of long slender thread-like structures called hyphae. Some hyphae are continuous tubes filled with multinucleated cytoplasm. Others have cross walls in their hyphae.

The cell walls of fungi are composed of chitin and polysaccharides. Most fungi are heterotrophic and absorb soluble organic matter from dead substrates as such known as saprophytes. Those dependent on living plants and animals are called parasites.

They can also live as symbionts – in association with algae as lichens and also with roots of higher plants as mycorrhiza. Vegetative means namely fragmentation, fission and budding lead to reproduction in fungi. Asexual reproduction is by spores known as conidia or sporangiospores or zoospores. Sexual reproduction is by oospores, ascospores and basidiospores. The various spores are produced in distinct structures known as fruiting bodies.

Bacteria are cosmopolitan in distribution. These organisms show the most extensive metabolic diversity. Bacteria may be autotrophic or heterotrophic in their mode of nutrition. Fungi reproduce both asexually and sexually. Fungi show a great diversity in structures and habitat. Most fungi are saprophytic in their mode of nutrition. They show asexual and sexual reproductions exist in fungi.

Most species of fungi live as multicellular filaments called hyphae, which form a mycelium while other species live as unicellular. They reproduce by means of spores. Fungi that reproduce through asexual spores and sexually-produced spores are called perfect fungi whereas fungi that reproduce only by asexual spores are called imperfect fungi (deuteromycetes). They do not have chlorophyll hence, they are heterotrophic organisms, absorbing foods into their hyphae.


What Is the Difference Between Fungus and Bacteria?

Fungi are multicellular, eukaryotic organisms, while bacteria are single-celled prokaryotes. The cells of fungi have nuclei that contain the chromosomes and other organelles, such as mitochondria and ribosomes. Bacteria are much smaller than fungi, do not have nuclei or other organelles and cannot reproduce sexually.

All eukaryotes, including plants, animals and fungi, have cells with nuclei and a large assortment of complex organelles that are used to carry out various biological functions. Fungi have cell walls and reproduce both sexually and asexually through the use of spores. They are unable to photosynthesize and must absorb nutrients by breaking down organic material. Many species of fungi play important roles in ecosystems by decomposing dead plants and animals. Scientists estimate that there are more than 2 million species of fungi on Earth.

Bacteria are one of the two main types of prokaryotes along with the archaea. Unlike fungi, their cells do not contain nuclei. Instead, their DNA is found on a circular chromosome that floats around in the cytoplasm. Bacteria generally reproduce through fission, producing two identical daughter cells. While bacteria can join together into complicated structures known as biofilms, they are not genuine multicellular organisms. Instead, each individual bacterium remains a separate organism.


Diseases

Both bacteria and fungi can cause human infections, but serious bacterial diseases occur more frequently than serious fungal infections. Common types of relatively minor fungal infections include athlete's foot, jock itch, ringworm of the nails, vaginal yeast infections and oral thrush. Examples of more serious, invasive fungal infections include Pneumocystis pneumonia, histoplasmosis and coccidioidomycosis, also known as valley fever. People with a weakened immune system are more susceptible to serious fungal infections than are those with a normal immune system.

Superficial bacterial infections often occur after minor cuts and scrapes. Deeper skin infections can cause abscesses or cellulitis. When bacteria evade the body's normal defenses, they can cause a wide range of infections. Common examples include urinary tract infections and strep throat. More serious infections most frequently caused by bacteria include pneumonia, bloodstream infections and bone infections. Many types of pathogenic bacteria produce toxins that cause some of their ill effects. Toxin production is uncommon among disease-causing fungi.


Which characteristic could you distinguish between bacteria and fungi? a. fungi are decomposers, but bacteria are not. b. bacteria are single-celled organisms, but most fungi are not. c. only fungi have cell walls, but bacteria do not. d. fungus only grow in moist locations, bacteria do not.

presence of hyphae in fungi , a long filamentous structure but plants lack hyphae.

Plants and fungi are both Eukaryotic but they are different from each other.

Plants are autotrophic i.e they can produce their own food by themselves through the process of photosynthesis but fungi are heterotrophs, they cannot synthesis their food on their own.

Plants cell walls are made up of cellulose and fungi cell walls are made up of chitin.

Fungi have hyphae, a filamentous structure but plants don't have.

D. The hyphae structures in the organism.

A hyphae can be described as long, feathery, branch like filamentous structure present in a fungus, actinobacterium or oomycete.

In most of the fungi, hyphae are considered as the main mode of vegetative growth, and they are together known as mycelium.

They play significant role in the absorption of nutrients (which are the products of digestion of complex organic matter) from the environment and transport them to different parts of body of the fungus.

Hyphae are absent in plants.

Thus, it is used to distinguish between plants and fungi.

A. The spores made by the fungi

The major phyla of the fungi are usually classified on the basis of characteristics of sexual structures.

For instance, the chytridiomycota produce zoospores, the blastocladiomycota undergo sporic meiosis, the ascomycota forms ascospores et cetera.

Fungi are mainly classified into seven phyla:

A. The spores made by the fungi

i dont think so but the teacher said it was a.

D. The shape of the fruiting bodies on the fungi

Fungi are eukaryotic in nature. This means they have a well defined nucleus and membrane bound organelles.

Fungi can be unicellular or multicellular organisms. They are reproduce either sexually by meiosis or asexually by the use of spores(condia) or through their mycelia in nature.

Fungi are mostly saprophytic organisms because they break down, live and feed on dead and decaying organic matter. Although there are some kinds of fungi that are parasitic in nature as well.

Fungi are classified based on the size and shape of their fruiting bodies.

Fruiting bodies are defined as structures present in fungi that is responsible for the formations of spore producing structures such as Asci and Basidia. Fruiting bodes are multicellular in nature.

Classification of fungi includes:

a. Chytridiomycota (True fungi). They reproduce sexually and asexually.

b. Zygomycota (Conjugated Fungi) e.g. Rhizopus stolonifer. The fungi usually reproduce asexually by producing sporangiospores

c. Ascomycota (The Sac Fungi) e.g. Aspergillus oryzae. They reproduce both asexually ( using spores also know as Condia ) and sexually ( using asci)

d. Basidiomycota (The Club Fungi) e.g Cryptococcus neoformans. They reproduce sexually.

e. Deuteromycota (The Imperfect Fungi). They reproduce asexually by the use of conidiospores.

f. Glomeromycota: They reproduce asexually.

Fungi have some beneficial and harmful uses.

Some beneficial uses of fungi are:

a. They are used in the manufacture of drugs . For example Penicillium as fungi is used to manufacture Penicillin which is an antibiotic for treating diseases.

b. They are used as sources of food. For example: Mushroom is a types of fungi that is consumed as food. It is a very healthy source of protein.

c. They are used industrially to manufacture food. For example: Yeast. Yeast is a type of fungi used in the production of foods such as Bread, Wine, Beer, Yoghurt. e.t.c

Some of the harmful effects of fungi are:

a. Some fungi have spoilage effects on plants and crops . For example: Mucor species , Rhizopus species (Bread Mold).

b. Some fungi cause diseases in human beings . For examples: Candida species.


Ascomycota: The Sac Fungi

Most fungi belong to the Phylum Ascomycota, which uniquely forms of an ascus, a sac-like structure that contains haploid ascospores.

Learning Objectives

Describe the ecology and the reproduction of Ascomycetes

Key Takeaways

Key Points

  • Ascomycota fungi are the yeasts used in baking, brewing, and wine fermentation, plus delicacies such as truffles and morels.
  • Ascomycetes are filamentous and produce hyphae divided by perforated septa.
  • Ascomycetes frequently reproduce asexually which leads to the production of conidiophores that release haploid conidiospores.
  • Two types of mating strains, a “male” strain which produces an antheridium and a “female” strain which develops an ascogonium, are required for sexual reproduction.
  • The antheridium and the ascogonium combine in plasmogamy at the time of fertilization, followed by nuclei fusion in the asci.
  • In the ascocarp, a fruiting body, thousands of asci undergo meiosis to generate haploid ascospores ready to be released to the world.

Key Terms

  • plasmogamy: stage of sexual reproduction joining the cytoplasm of two parent mycelia without the fusion of nuclei
  • Ascomycota: a taxonomic division within the kingdom Fungi those fungi that produce spores in a microscopic sporangium called an ascus
  • ascus: a sac-shaped cell present in ascomycete fungi it is a reproductive cell in which meiosis and an additional cell division produce eight spores
  • ascospore: a sexually-produced spore from the ascus of an Ascomycetes fungus
  • conidia: asexual, non-motile spores of a fungus, named after the Greek word for dust, conia also known as conidiospores and mitospores
  • antheridia: a haploid structure or organ producing and containing male gametes (called antherozoids or sperm) present in lower plants like mosses and ferns, primitive vascular psilotophytes, and fungi
  • ascogonium: a haploid structure or organ producing and containing female gametes in certain Ascomycota fungi
  • ascocarp: the sporocarp of an ascomycete, typically bowl-shaped
  • ascomycete: any fungus of the phylum Ascomycota, characterized by the production of a sac, or ascus, which contains non-motile spores

Ascomycota: The Sac Fungi

The majority of known fungi belong to the Phylum Ascomycota, which is characterized by the formation of an ascus (plural, asci), a sac-like structure that contains haploid ascospores. Many ascomycetes are of commercial importance. Some play a beneficial role, such as the yeasts used in baking, brewing, and wine fermentation, plus truffles and morels, which are held as gourmet delicacies. Aspergillus oryzae is used in the fermentation of rice to produce sake. Other ascomycetes parasitize plants and animals, including humans. For example, fungal pneumonia poses a significant threat to AIDS patients who have a compromised immune system. Ascomycetes not only infest and destroy crops directly, they also produce poisonous secondary metabolites that make crops unfit for consumption. Filamentous ascomycetes produce hyphae divided by perforated septa, allowing streaming of cytoplasm from one cell to the other. Conidia and asci, which are used respectively for asexual and sexual reproductions, are usually separated from the vegetative hyphae by blocked (non-perforated) septa.

Asexual reproduction is frequent and involves the production of conidiophores that release haploid conidiospores. Sexual reproduction starts with the development of special hyphae from either one of two types of mating strains. The “male” strain produces an antheridium (plural: antheridia) and the “female” strain develops an ascogonium (plural: ascogonia). At fertilization, the antheridium and the ascogonium combine in plasmogamy without nuclear fusion. Special ascogenous hyphae arise, in which pairs of nuclei migrate: one from the “male” strain and one from the “female” strain. In each ascus, two or more haploid ascospores fuse their nuclei in karyogamy. During sexual reproduction, thousands of asci fill a fruiting body called the ascocarp. The diploid nucleus gives rise to haploid nuclei by meiosis. The ascospores are then released, germinate, and form hyphae that are disseminated in the environment and start new mycelia.

Release of ascospores: The bright field light micrograph shows ascospores being released from asci in the fungus Talaromyces flavus var. flavus.

Lifecycle of an ascomycete: The lifecycle of an ascomycete is characterized by the production of asci during the sexual phase. The haploid phase is the predominant phase of the life cycle.


Column: Biology basics: What is a virus, bacteria, fungus? And how can we kill them?

With the coronavirus on everyone’s mind, let’s go back to some basics. Like what is a virus and how do we get rid of it? Modern medicine seems to cure most anything, so why is it so hard to destroy the coronavirus?

There are three major “pathogens” (biological structures that can make humans ill). They are bacteria (bacterium), fungi (fungus) and viruses (virus). Each one is unique in its structure and complexity. Therefore, the way to destroy each of them is also unique.

We are exposed to thousands, if not millions, of unique pathogens. Our immune system must learn how to destroy each and every one. When we are born, we have almost no immune system we are incredibly vulnerable to infection and sickness. We must build up our immune system with antibodies. Antibodies are how the immune system can identify, tag, and destroy the pathogens making a person sick. The only way an immune system can build up antibodies is to be exposed to a pathogen and “learn” how to identify, tag, and destroy the pathogen. The only shortcut to this is when a mother can pass some antibodies to a nursing infant through her breast milk. (This is only one of the many reasons why a newborn should be breast fed.)

However, once our immune systems have the antibodies needed to identify, tag, and destroy a specific pathogen, it will “remember” that pathogen. So, the next time you are exposed to it, your immune system will produce the antibodies to destroy the pathogen much quicker, ideally even before you feel sick.

Sometimes our immune systems cannot do it on its own, that is where medicine is required. Remember, there are bacteria, fungal and viral pathogens.

First, fungi tend to be external organisms that live on surfaces. Mold, mushrooms, and mildew are some classic examples and good to use as a reference. They grow in dark, moist places on decaying matter. The hypha or roots burrow into the organic matter to extract the nutrients it needs for life. Athletes foot, jock itch and yeast infections are all common pathogens many of us have suffered. Although, internally fungi are lethal, they are rare. Most external fungi can be destroyed with an anti-fungal cream or pill. Fungi tend to be on the low side of complexity and relatively easy to kill.

Bacterial pathogens are individual living organisms. They are the “germs” that we think of swimming around under a microscope. There are millions of varieties of them. They live on their own, on surfaces within the air, in foods and water. Many ear, throat, and sinus infections are bacterial. Fortunately, our immune system is pretty good at identifying these foreign organisms living within our bodies and can destroy them on its own. And if it cannot, a doctor can prescribe an antibiotic (penicillin) to finish the job.

On the other hand, viruses are non-living, they are “DNA pirates.” They cannot live or reproduce on their own. Think of a virus as a blob of grease or oil with a single strand of DNA within it. No nucleus, no organelles, just a microscopic ball of fat with a code to cause some biological mutiny.

Viruses require a host cell for reproduction. The virus does this by taking over a host cell and forcing the cell to reproduce the virus and its fatty shell, much like a pirate hijacking a ship for its own purposes. Unfortunately, the cell will no longer be able to perform the life-sustaining job it was intended to be doing hence you feel sick. The host cell will continue to perform the pirate’s task, reproduce the virus, until it destroys itself. Then, liberating more DNA pirates to repeat the process.

The fact that the virus lives “inside” the cell makes it hard for the immune system to identify the pathogen, let alone destroy it. The only way to destroy the virus is to destroy the cell itself. The pirate will never leave the ship, the ship must be destroyed to kill the pirate.

This is what our immune systems does – anti-bodies identify, tag, and destroy the living cells that have the virus within them. This explains our symptoms which can range from minor aches and pains to lethal tissue and organ damage. Your immune system is literally destroying your own cells.

Fortunately, we have billions of cells and our immune system can be very targeted once the anti-bodies have figure out which cells have been pirated by the virus. White blood cells can then effectively destroy only the pirated cells and recovering will begin.

A major problem with the coronavirus in humans is our immune systems have a hard time identifying which cells have been pirated by the virus and which cells are still healthy. Human immune systems seem to be over-reacting and destroying all the surrounding cells. Since the virus is often found in the lungs, heart, and kidneys these are the organs that seem to be suffering the most.

So how do we destroy the coronavirus? They only thing that can destroy a virus is our own immune system. The medical field has had little success in developing anti-viral medications. We can only support our immune system to learn quicker, to produce the antibodies needed and then the immune system can become much more targeted.

Vaccines do this by providing a weakend version for the immune system to learn from. Anti-body therapy takes the anti-bodies from one immune system that has already learned how to identify the virus and directly gives it to an “un-learned” immune system.

Unfortunately, we do not have any solutions yet! So, the best way to be healthy is to not get sick in the first place. Stay away from the pirates! You all know what to do, washing your hand, social distance, etc. Be safe.


Further reading and references

This factsheet is adapted from the Soil Biology Basics information series. The New South Wales Department of Primary Industries has further soil biology information, including the complete Soil Biology Basics series (online)

Authors: Greg Reid and Percy Wong (New South Wales Department of Primary Industries), 2005

Revised:Stephanie Alt (New South Wales Department of Primary Industries), 2013

The National Soil Quality Monitoring Program is being funded by the Grains Research and Development Corporation, as part of the second Soil Biology Initiative.
The participating organisations accept no liability whatsoever by reason of negligence or otherwise arising from the use or release of this information or any part of it.