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News

Keep up to date with the latest microbiology news. Most stories are linked to the full newspaper article.

Latest Videos

Educational videos featuring microbial techniques.

Latest Podcasts

Interviews with leading microbiologists about their latest research.

For Teachers

Information and advice on all aspects of microbiology teaching - both theory and practice is just a click away.

Microbes and the outdoors

The function of microbes as tiny chemical processors is to keep the life cycles of the planet turning.

Creation of Fossil Fuels

Under the right conditions carbon-based fossil fuels, coal, oil and gas are formed. These are mined from the ground.

Fossil Fuels releasing carbon

Carbon is released into the atmosphere when fossil fuels are burned

Decomposers

More carbon is released into the atmosphere by respiration of decomposers.

Photosynthesis

Photosynthetic microbes and green plants take in carbon during photosynthesis and produce glucose (a sugar).

Introducing microbes

Micro-organisms can be friend or foe but most importantly, we all need them to live!

Microbes and the human body

Ever wondered why when we are surrounded by microbes we are not ill all the time?

Microbes and food

Food for thought - bread, chocolate, yoghurt, blue cheese and tofu are all made using microbes.

Overview

An overview of the world of microbes!

Bacteria

More than just pathogens - can be friend or foe.

The different bacterial shapes:

a. bacillus (rod), b. coccus (spherical), c. spirillum (spiral), d. spirochaete (corkscrew), e. vibrios (comma), f. chain of cocci, g. cluster of cocci, h. pair of cocci, i. chain of bacilli

Antibiotic resistance

Artwork of bacterial cells becoming resistant to antibiotics. This resistance is acquired from a donor cell's plasmid (circular unit of deoxyribonucleic acid, DNA), which has resistance seen at upper left (red/yellow, red is resistance). Viral transmissio

Bacillus anthracis spores

This bacterium causes anthrax in farm animals and less commonly in humans. Spores can survive for many years and are resistant to extremes of heat, cold and drying.

Reproduction through Binary Fission

One becomes two ... two becomes four ... four becomes eight This means in 8 hours, the number of bacteria will have risen to a colossal 16,777216!

Viruses

Smallest of all the microbes but are they alive?

Computer artwork of a typical virus particle which is icosahedral in shape.

The virus consists of a core of RNA (ribonucleic acid, green) enclosed in a capsid, or protein coat (blue spheres). Surrounding the capsid is a glycoprotein envelope (pink and green). Inserted in the envelope are surface proteins (orange spheres), which h

T2 bacteriophage viruses (orange) attacking an Escherichia coli bacterium.

Each phage consists of a large DNA- containing head and a tail composed of a tube-like central sheath with several fibres.

Herpes simplex virus infection.

A section through a cell being destroyed by herpes simplex virus infection. At centre is a large cluster of viral capsids (protein coats, red) which the cell has produced at the direction of the virus's genetic material.

Fungi

More than just mushrooms.

The yeast Saccharomyces cerevisiae.

Budding yeast Saccharomyces cerevisiae. Scars yellow can be seen on the surface. It is used in the production of beer, wine and bread.

Macroscopic filamentous Fly agaric fungus (Amanita)

Macroscopic filamentous Fly agaric fungus (Amanita)

Multicellular filamentous mould.

Rhizopus nigricans growing on bread left in a moist plastic bag for 7 days. Tangled mycelium are visible as well as sporangia bearing spores.

Honey mushroom fungus

The largest organism in the world, when measured by area, is the Honey mushroom fungus, Armillaria.

Protozoa

Microbes with a taste for poo and so much more.

Amoeba proteus protozoa

These are freshwater single-celled microbes that feed on bacteria and smaller protozoa. They use pseudopodia (cytoplasmic extensions) to engulf their food and for locomotion.

The test (shell) of the British formaminiferan, Elphidium crispum.

Foraminifera are single-celled protozoa which construct and inhabit shells. The shells are usually divided into chambers which are added during growth. These shells are made of calcium carbonate but some are made from sand and even silica.

An illustration of the protozoan Trypanosoma brucei.

This illustration depicts Trypanosoma brucei moving past human red blood cells in the blood. It is motile and has a single flagellum for locomotion.

Vorticella ciliate in compost heap.

Vorticella is bell- shaped with a contractile stalk (bottom) to anchor itself to the surface. It has a flattened top with a mouth surrounded by a wreath of cilia (tiny hair-like projections). By beating these cilia the organism causes the water to swirl l

Paramecium a protozoan

This single-celled organism lives in freshwater habitats. It is covered in cilia, short hair-like structures used for swimming and for wafting food into its groove-like mouth (centre).

Filaments of Spirogyra

Green algae can make their own food through a process of photosynthesis. They are at the beginning of the food chain and are known as primary producers.

Filaments of the alga Spirogyra

Green algae can make their own food through a process of photosynthesis. They are at the beginning of the food chain and are known as primary producers.

Chlamydomonas.

Chlamydomonas is a unicellular green alga. It is motile and has two tail-like flagella that it uses for locomotion.

Algal blooms lining the shores (light green).

These blooms occur as a result of a change in the nutrient levels of the river. Contamination by sewage or fertilisers can increase the water's mineral content, which accelerates the growth of all plants, particularly aquatic algae.

A selection of diatoms

Diatoms are single-celled photosynthetic algae. Their cell walls contain a hard substance called silica.

Dulse (red) seaweed - Rhodymenia palmata

Rhodymenia palmata is an edible alga. Dulse is very popular in Ireland, where it is often mixed with potatoes and butter, adding a salty, savoury bite to fried potato champ.

Archaea

First found existing on the edge of life.

Sulfolobus

Sulfolobus is an extremophile that is found in hot springs and thrives in acidic and sulphur-rich environments.

Methanosarcina rumen (green with red cell walls).

Methanosarcina rumen is anaerobic, and is found in places with little or no oxygen. It is a methane- producing organism that digests decaying organic matter. It is found in the rumen of a group of animals called ruminants such as cattle and sheep.

Staphylothermus marinus

Staphylothermus marinus is an extremophile found in deep ocean hydrothermal vents, thriving on volcanic sulphur and surviving in water temperatures of up to 98°C

Halococcus salifodinae

Halococcus salifodinae is found in water with high concentrations of salt. These high salt concentrations would be deadly to most other forms of life, and so H. salifodinae is also known as an extremophile.

Methanococcoides burtonii

Methanococcoides burtonii is an extremophile and was discovered in 1992 in Ace Lake, Antarctica, and can survive in temperatures as low as -2.5 °C.

Artwork of a human figure surrounded by disease-causing microbial pathogens,

BRYSON BIOMEDICAL ILLUSTRATIONS / CUSTOM MEDICAL STOCK PHOTO / SCIENCE PHOTO LIBRARY

Immune system

An infection can be seen as a battle between the invading pathogens and host. How does the immune system work?

A macrophage

A macrophage (type of phagocyte) engulfing a bacterium. A macrophage (brown) which is a type of phagocyte engulfing a bacterium (blue). The nucleus of the macrophage is red.

A blood clot

© CNRI / Science Photo Library

Computer artwork of bacteria

Computer artwork of bacteria (blue and green) on human skin.

Staphylococcus aureus

Staphylococcus aureus bacteria (yellow) sticking to the mucus (blue) on the hair-like cilia.

Macrophage

Macrophage (yellow) engulfing Escherichia coli bacteria (pink rods). This process is called phagocytosis.

Illustration of antibody action on invading bacteria. The antibodies (Y-shaped, red) are binding to and destroying the bacteria (brown) as these organisms move into the blood vessel at lower right. The blood vessel also contains a white blood cell (blue)

CARLYN IVERSON / SCIENCE PHOTO LIBRARY

Close-up of a running nose,

BSIP, KRASSOVSKY / SCIENCE PHOTO LIBRARY

Transmission by person to person contact.

Measles, mumps and tuberculosis can be spread by coughing or sneezing. A cough or a sneeze can release millions of microbes into the air in droplets of mucus or saliva which can then infect somebody else if they breathe in the infected particles.

Transmission by food

Chicken skin from a retail package contaminated with bacteria; some of the bacteria are Salmonella. Cooking the chicken properly will kill the bacteria and make the meat safe to eat.

Transmission by contaminated wastewater flowing from a pipe into a lagoon.

Some diseases are caused by drinking water that is contaminated by human or animal faeces, which may contain disease-causing microbes.

Insects can also transmit pathogens to food.

House flies are very good at spreading Salmonella and E.coli O157. They feed on faecal waste and transfer microbes from their feet and other body parts to food.

Transmission by fomites (non-living objects) such as barbed wire.

A puncture wound on the finger caused by a prick from rusted barbed wire may result in tetanus due to infection by spores of the bacterium Clostridium tetani. The spores live mainly in soil and manure, but are also found on dirty or rusting metal objects.

Close-up of a doctor giving an influenza (flu) vaccination,

JAMES KING-HOLMES / SCIENCE PHOTO LIBRARY

MMR vaccine

MMR vaccine being drawn into a syringe. This combined vaccine protects children from three viral diseases: measles, mumps and rubella.

Notes on and a drawing of the original culture plate of the fungus Penicillium notatum, made by the Scottish bacteriologist Sir Alexander Fleming whilst working at St. Mary's Hospital, Paddington, London. Fleming discovered in 1928 that secretions from Pe

ST MARY'S HOSPITAL MEDICAL SCHOOL / SCIENCE PHOTO LIBRARY

The effects of the antibiotic drug ceftazidine on Staphylococcus aureus bacteria.

The antibiotic kills the bacteria (red) by causing the cell wall to disintegrate (yellow remnants).

Food poisoning

There are probably at least a million cases of microbial food poisoning in the UK every year costing an estimated £1.5b a year - how can anything as small as a microbe cause all this trouble?

The bacterium Campylobacter jejuni is a common cause of food poisoning. Contaminated poultry, meat and milk are sources of infection. It takes about 3 days for the symptoms of diarrhoea, stomach cramps and fever to develop.

A. DOWSETT, HEALTH PROTECTION AGENCY / SCIENCE PHOTO LIBRARY

Mouldy bread. The mould Penicillium is penetrating the bread, digesting it and absorbing nutrients,

CORDELIA MOLLOY / SCIENCE PHOTO LIBRARY

Penicillium mould growing on bread

The yellow fibrous structures are hyphae, which make up the main body of the fungus. They penetrate the bread and absorb nutrients. The small green dots are the conidia, the spores of the mould.

Producers

Microbes ferment sugar to make energy for themselves - luckily for us foods like bread and yoghurt can be made by microbial fermentations.

Bread yeast - Saccharomyces cerevisiae

Used to make bread. Yeast is a single-celled fungus. It is able to ferment sugar, producing alcohol and carbon dioxide in the process. It has long been used to make beer and wine as well as bread (the carbon dioxide causes the dough to rise).

Nitrogen cycle

Waste products (undigested food, urine and faeces) and dead organisms which contain nitrogen compounds are added to the soil.

Ammonification (decay)

The decomposers - certain soil bacteria and fungi e.g. ammonifying bacteria - break down proteins in dead organisms and animal wastes, releasing ammonium ions.

Nitrification

Nitrification is a two-step process that is carried out by the nitrifying bacteria. Ammonia or ammonium ions are oxidized first to nitrites and then to nitrates.

Denitrification

Nitrates are reduced to nitrogen gas by denitrifying bacteria.

Nitrogen fixation

Atmospheric fixation - this occurs spontaneously due to lightning. Only a small amount is fixed this way. Industrial fixation - the Haber process is used to make nitrogen fertilizers. This is very energy inefficient.

Biological fixation

Nitrogen fixing bacteria fix 60% of nitrogen gas. Some nitrogen fixing bacteria e.g. Rhizobium live in the root nodules of legumes. Some nitrogen fixing bacteria e.g. Azotobacter are free living in the soil. Nitrogen in the air

Primary producers

Organisms that make their own food are called primary producers and are always at the start of the food chain. Animals and micro-organisms like fungi and bacteria get energy and nutrients by eating other plants, animals and microbes.

Food chain

Overview

Photosynthesis

Photosynthetic organisms like algae, cyanobacteria and plants are capable of using light energy which is trapped by chlorophyll, to convert carbon dioxide and water into oxygen and glucose (food). This process is called photosynthesis.

Primary producers

Organisms that make their own food are called primary producers and are always at the start of the food chain. Animals and micro-organisms like fungi and bacteria get energy and nutrients by eating other plants, animals and microbes.

Aerobic respiration

Organisms release energy from food (glucose), as well as carbon dioxide and water in the process of aerobic respiration. This energy is used to do the work needed to keep cells and organisms alive. Aerobic respiration requires oxygen.

Decomposition

The decomposers (fungi and soil bacteria) obtain their energy and nutrients from the dead bodies and waste products of other organisms. As dead bodies and waste products break down, they release essential nutrients into the soil.

Observing microbes

Information on observing different types of microbes

Microalgae biofuel research. Researcher adjusting a bioreactor to culture microalgae. Bioreactors are used to maintain a specific environment. They allow all aspects of the environment, such as pH, temperature, and light, to be controlled and maintained a

HUBERT RAGUET / LOOK AT SCIENCES / SCIENCE PHOTO LIBRARY

The common soil fungus Trichoderma.

It secretes huge quantities of the enzyme cellulase. Cellulase speeds up the breakdown of cellulose into sugars.

Mosquito feeding on human blood. There is concern among some scientists that climate change will cause an increase in the number of some mosquito-borne diseases,

SINCLAIR STAMMERS / SCIENCE PHOTO LIBRARY

Bluetongue virus (BTV)

Bluetongue virus causes bluetongue disease in domestic and wild ruminants is carried by a midge and transmitted to mammals through a bite.

Microbe Passports

Take a peek down the microscope and explore further the secret world of microbes.

Microbes and basic principles

Microbes are extremely versatile and, as living organisms, can be used to teach many of the basic principles of biology. They can also be used to demonstrate How Science Works.

Sterilising a wire loop over a Bunsen burner,

MARTYN F. CHILLMAID / SCIENCE PHOTO LIBRARY

Preparation of media and cultures

Recipes for microbial culture media.

Practical advice

A selection of safe, tired and tested microbiology investigations that are suitable for key stages 3 and 4 safe and equivalent Scottish qualifications.

Resources

Free resources on hot topics such as TB, AIDS and microbes and climate change.

Safety Information

A guide to the safety considerations when handling microbes in the lab.

Risk assessment

How to assess risk before carrying out practical microbial work.

Good microbiological laboratory practice (GMLP)

What is GMLP and why is it necessary?

Spillage management

How to manage spills safely.

For Teachers

Information and advice on all aspects of microbiology teaching - both theory and practice is just a click away.

For Students

Curious about microbiology? Ever wondered what a microbe is? What they do? The answers are here.

Observing microbes

Information on observing different types of microbes

The desmid Micrasterias. The desmids are a group of freshwater unicellular green algae characterised by their intricately- shaped cell walls and symmetrical shapes,

POWER AND SYRED / SCIENCE PHOTO LIBRARY

Algae

Microbial powerhouses essential for life

The desmid Micrasterias. The desmids are a group of freshwater unicellular green algae characterised by their intricately- shaped cell walls and symmetrical shapes,

POWER AND SYRED / SCIENCE PHOTO LIBRARY

Chlamydomonas.

Chlamydomonas is a unicellular green alga. It is motile and has two tail-like flagella that it uses for locomotion.

Bacteria

Observing fungi in a Petri dish

A swab from a bin spread directly onto nutrient agar. Colonies differ in their shape, size, colour and texture. Can you count how many different colony types there are? Use the diagrams on colony morphology to help you interpret your plate,

MICROBIOLOGY SOCIETY

A cough that was aimed directly onto nutrient agar. Colonies differ in their shape, size, colour and texture. Can you count how many different colony types there are? Use the diagrams on colony morphology to help you interpret your plate,

MICROBIOLOGY SOCIETY

sample of liquid soap spread onto nutrient agar and a swab from a bar of solid soap also spread onto nutrient agar. Soaps are not designed to kill microbes. They help to wash them of your skin, better than water alone. Why do you think that the solid soa

MICROBIOLOGY SOCIETY

A streak plate to isolate single colonies of a specific bacterium found living on a sample of paper. Paper is not a good object for bacteria to live on as it cannot sustain their growth. The bacteria found on the paper are know as transient i.e. they are

MICROBIOLOGY SOCIETY

Resources

Free resources on hot topics such as TB, AIDS and microbes and climate change.

Colony morphology,

MICROBIOLOGY SOCIETY

Plate 1 contains a circular piece of bread that has been allowed to go mouldy. There is overgrowth on the plate and many different mould species can be seen. In between the two plates is a toothpick which was used to isolate the spores from one of the mou

MICROBIOLOGY SOCIETY

Two malt extract agar plates were exposed to the air outdoors and two malt extract plates were exposed to the air indoors. Use the diagrams on colony morphology to help you interpret the plates. Why do you think there are more moulds on the plates exposed

MICROBIOLOGY SOCIETY

An excellent example of fungal mycelium. Use the diagrams on colony morphology to help you the plate,

MICROBIOLOGY SOCIETY

Microscope,

Learn how a microscope works and how to effectively use it in practice.

Microbial recipes

Food for thought - bread, ginger beer and yoghurt are all made using microbes. Download our recipes and make your own tasty microbial treats.

For Students

Curious about microbiology? Ever wondered what a microbe is? What they do? The answers are here.

Revision tips

Key facts and important ideas that will help with last minute revision about microbiology.

Microbe Passports

Take a peek down the microscope and explore further the secret world of microbes.

STI Quiz and Tutorial

With STIs on the rise, it is important that we are all STI aware. Take the quiz and see how much you know.

Microbial recipes

Food for thought - bread, ginger beer and yoghurt are all made using microbes. Download our recipes and make your own tasty microbial treats.

Herpes simplex virus infection.

A section through a cell being destroyed by herpes simplex virus infection. At centre is a large cluster of viral capsids (protein coats, red) which the cell has produced at the direction of the virus's genetic material.

Vorticella ciliate in compost heap

Vorticella is bell- shaped with a contractile stalk (bottom) to anchor itself to the surface. It has a flattened top with a mouth surrounded by a wreath of cilia (tiny hair-like projections). By beating these cilia the organism causes the water to swirl l

Grants

Grants of up to £1,000 to support microbiology teaching initiatives and events.

Contacts

Get in touch with the Microbiology Society.

Credits

A list of attributions and thanks for assets used on this website.

A blood clot

© CNRI / Science Photo Library