BACTERIA BASICS

 There are two kingdoms of bacteria: Archaebacteria and Eubacteria  All bacteria are unicellular prokaryotes.

WHERE ARE BACTERIA FOUND?  Most bacteria like a warm, dark, and moist environment. They are found almost everywhere: -water-air -food-soil - inside the body - skin -on most objects

BACTERIA  Many bacteria are so small that a million of them, laid end-to-end, would measure no more than about five centimeters (two inches).  They tend to multiply very rapidly under favorable conditions, forming colonies of millions or even billions of organisms within a space as small as a drop of water.

REPRODUCTION OF BACTERIA  How quickly bacteria reproduce depends on how desirable the conditions are.  Bacteria can rapidly reproduce themselves in warm, dark, and moist conditions.

REPRODUCTION OF BACTERIA  Some can reproduce every 20 minutes  (one bacterium could be an ancestor to one million bacteria in six hours)

REPRODUCTION OF BACTERIA  Asexual reproduction- reproduction of a living thing from only one parent (only one set of DNA)  Examples: binary fission, budding, or regeneration

REPRODUCTION OF BACTERIA  Bacteria most commonly reproduce by binary fission, the process by which a single cell divides to produce two new cells.  How?  The one main chromosome makes a copy of itself. Then it divides into two.

BINARY FISSION Bacteria dividing Completed Reproduction of Bacteria

BACTERIA SURVIVAL  endospore- a thick walled, protective structure that forms inside a bacterial cell when conditions are unfavorable for survival  It acts like a force field. The bacterium can stay dormant for a long period of time.

Endospore-the black section in the middle  highly resistant structures  can withstand radiation, UV light, and boiling at 120 degrees C for 15 minutes Bacteria Survival

BACTERIA SURVIVAL  The endospore encloses all the genetic materials and some cytoplasm  This means bacteria can withstand boiling, freezing, and extremely dry conditions  The endospore allows the bacteria to survive for many years.

Most bacteria are harmless or useful. Bacteria grow in the stomach of a cow to break down grass and hay. Some are used to make antibiotics. Some bacteria help make insulin. Some are used to make industrial chemicals. Helpful Bacteria

HELPFUL BACTERIA Bacteria is used to treat sewage. Organic waste is consumed by the bacteria, used as nutrients by the bacteria, and is no longer present to produce odors, sludge, pollution, or unsightly mess.

HELPFUL BACTERIA  Certain kinds of bacteria are also essential in the decay and decomposition of waste materials.  Such bacteria are known as decomposers.  Decomposers attack dead materials and break them down into simpler forms that can be used as nutrients by plants.

THE GOOD GUYS  Remember: most bacteria are harmless or useful. (decomposers)  Some help you to digest food, make vitamins for you, or prevent harmful bacteria from making you sick.  Bacteria are involved in the production of many foods eaten by humans.

HELPFUL BACTERIA  Bacteria are used in making the following foods:  Cheese  Yogurt  Buttermilk  Sour cream

HELPFUL BACTERIA  Bacteria are used in making the following foods:  Apple cider  Sourdough bread

HELPFUL BACTERIA  Bacteria are used in making the following foods:  Olives  Sauerkraut  Pickles  Vinegar

HELPFUL BACTERIA  Bacteria make possible the digestion of foods in many kinds of animals.  In humans, bacteria known as Escherichia coli ( E. coli ) occur everywhere in the digestive system, aiding in the breakdown of many kinds of foods.  Bacteria are also responsible for the production of vitamin K and certain B vitamins.

E.coli on small intestines Helpful Bacteria

HARMFUL BACTERIA The Bad Guys  Some bacteria cause food to spoil.  The wastes they produce spoil the food.  Since bacteria reproduce better in warm temperatures, you must keep food cold, that is why we use refrigerators.

CONTROLLING BACTERIA 3 ways to control bacteria in food: 1) Canning 2) Pasteurization 3) Dehydration

CONTROLLING BACTERIA 1) Canning- the process of sealing food in airtight cans or jars; removes oxygen, destroys enzymes, prevents the growth of undesirable bacteria, yeasts, and molds

CONTROLLING BACTERIA 2 ) Pasteurization- the process of heating a beverage or other food, such as milk, in order to kill microorganisms that could cause disease, spoilage, or undesired fermentation

CONTROLLING BACTERIA 3) Dehydration- removing water from food; bacteria can’t grow when water is removed. (Remember: Bacteria are living things. Water is one of the needs of all living things.)

HARMFUL BACTERIA  Human tooth with accumulation of bacterial plaque (smooth areas) and calcified tartar (rough areas)

HARMFUL BACTERIA  some bacteria cause diseases  animals can pass diseases to humans communicable disease – a disease passed from one organism to another

 Diseases may be passed from one organism to another via:  Air  Touching clothing, food, silverware, or a toothbrush  Drinking water that contains bacteria

TREATMENTS  Vaccines help prevent some bacterial infections.  Antibiotics, such as Amoxicillin, help cure some bacterial infections.

TREATMENTS FOR BACTERIAL INFECTIONS  Antibiotic ointments and sprays kill bacteria in cuts and scrapes

CONTROLLING BACTERIA ANTISEPTIC VS. DISINFECTANTS Antiseptic- chemicals that kill bacteria on living things (OK to be on your body)  means – “against infection”  Examples: iodine, hydrogen peroxide, alcohol, soap, mouthwash

CONTROLLING BACTERIA ANTISEPTIC VS. DISINFECTANTS Disinfectants- stronger chemicals that destroy bacteria on objects or nonliving things (NOT OK to put on/in your body) Examples: Lysol, bleach

SOME BACTERIAL DISEASE DiseaseScientific NameContracted through Food _________________ Salmonella Escherichia coli (E coli) Contaminated eggs, poultry, meat Contaminated food, especially undercooked ground beef __________ disease Borrelia burgdorferibite of infected blacklegged (or deer) ticks Tetanus (____________) Clostridium tetanifound in soil Tuberculosis (____) Mycobacterium tuberculosis breathing infected air Strep ___________ Streptococcus pyogenes close contact with the saliva or nasal secretions from an infected individual, typically in the form of airborne respiratory droplets

SOME BACTERIAL DISEASES  Food poisoning

SALMONELLA  Salmonella, the name of a group of bacteria, is one of the most common causes of food poisoning in the United States.  Usually, symptoms last 4-7 days and most people get better without treatment.  Salmonella is killed by cooking and pasteurization.

SALMONELLA Sources Food: Contaminated eggs, poultry, meat, unpasteurized milk or juice, cheese, contaminated raw fruits and vegetables (alfalfa sprouts, melons), spices, and nuts Animals and their environment: Particularly reptiles (snakes, turtles, lizards), amphibians (frogs), birds (baby chicks) and pet food and treats. Symptoms Diarrhea, fever, abdominal cramps, vomiting Duration of Illness 4-7 days

ESCHERICHIA COLI ( E COLI )  E. coli is the name of a type of bacteria that lives in your intestines and in the intestines of animals.  Although most types of E. coli are harmless, some types can make you sick.  The worst type of E. coli, known as E. coli O157:H7, causes bloody diarrhea and can sometimes cause kidney failure and even death.

ESCHERICHIA COLI ( E COLI ) Sources Contaminated food, especially undercooked ground beef, unpasteurized (raw) milk and juice, soft cheeses made from raw milk, and raw fruits and vegetables (such as sprouts) Contaminated water, including drinking untreated water and swimming in contaminated water Animals and their environment : particularly cows, sheep, and goats. If you don’t wash your hands carefully after touching an animal or its environment, you could get an E. coli infection Feces of infected people Incubation Period 1-10 days Symptoms Severe diarrhea that is often bloody, severe abdominal pain, and vomiting. Usually, little or no fever is present. Symptoms of HUS include decreased urine production, dark or tea-colored urine, and facial pallor. Duration of Illness 5-10 days. Most people will be better in 6-8 days.

LYME DISEASE  Lyme disease is caused by the bacterium Borrelia burgdorferi and is transmitted to humans through the bite of infected blacklegged (or deer) ticks.

TETANUS (LOCKJAW)  Tetanus typically arises from a skin wound that becomes contaminated by a bacterium called Clostridium tetani, which is often found in soil.

TETANUS (LOCKJAW)  The disease has been called lockjaw since the muscle spasms in the face and neck can lead to the inability to open the mouth, and this is one of the most common symptoms of tetanus.

TETANUS (LOCKJAW)  In the United States, most cases of tetanus follow a contaminated cut or deep puncture injury, such as a wound caused by stepping on a nail. Once the bacteria are in the body, they produce a neurotoxin. The toxin can travel throughout the body via the bloodstream and lymph system. The toxin interferes with the normal activity of nerves throughout the body.

TUBERCULOSIS  Tuberculosis (TB) is an infection, primarily in the lungs (a pneumonia), caused by bacteria called Mycobacterium tuberculosis. It is spread usually from person to person by breathing infected air during close contact.

STREP THROAT Streptococcus pyogenes causes Streptococcal pharyngitis, streptococcal tonsillitis, or streptococcal sore throat (known as strep throat) is a type of pharyngitis. It affects the pharynx including the tonsils and possibly the larynx.

STREP THROAT  Strep throat is a contagious illness that is spread from person-to-person.  Strep throat symptoms generally include fever, sore throat, swollen lymph nodes in the neck and redness and swelling of the throat and tonsils. White or yellow patches on the tonsils (signifying pus) are also often present. Strep throat may produce mild or severe symptoms.

STREP THROAT  Strep throat most commonly occurs between late fall and early spring. It is more widespread during the school year when groups of students are present within an enclosed space.  Though strep throat is the most common bacterial cause of sore throat, it is important to note that most cases of sore throat are in fact due to a viral infection (caused by a virus).

STREP THROAT  It is usually transmitted by close contact with the saliva or nasal secretions from an infected individual, typically in the form of airborne respiratory droplets. For this reason, it is frequently seen in situations where individuals are in close proximity to each other, as in schools, college campuses, military barracks, day care centers, and family households.

SOME BACTERIAL DISEASE DiseaseScientific NameContracted through Food poisoning Salmonella Escherichia coli (E coli) Contaminated eggs, poultry, meat Contaminated food, especially undercooked ground beef Lyme disease Borrelia burgdorferibite of infected blacklegged (or deer) ticks Tetanus (Lockjaw) Clostridium tetanifound in soil Tuberculosis (TB) Mycobacterium tuberculosis breathing infected air Strep throat Streptococcus pyogenes close contact with the saliva or nasal secretions from an infected individual, typically in the form of airborne respiratory droplets

Spiral Rod-shaped Round Bacteria are classified by shape into 3 groups: Bacteria

Bacillus anthracis – (rod-shaped) Neisseria meningitidis (round) 3 Shapes of Bacteria: Leptospira interrogans – (spiral-shaped)

spirillum-one (singular) spirulla –more than one (plural)

bacillus (singular) bacilli (plural)

coccus (singular) cocci (plural)

ARCHAEBACTERIA  But some bacteria prefer cold temperatures as low as freezing (0°C or 32°F), and others require very hot temperatures such as those found in hot springs (50°C to 90°C or 120°F to 200°F).

ARCHAEBACTERIA  The most extreme conditions in which bacteria have been found are around the hydrothermal vents near the Galapagos Islands.  The temperatures near these cracks in the ocean floor is about 350°C (660°F), an environment just right, apparently, for the bacteria that live there.