microbes test 1

roles of microbes

• pathogens

• food chain

• digestion

• foods and fermentation

• antibiotics

• biotechnology

• bioremediation

• disease research

roles of microbes in food chain

• Autotrophs: organisms that use sun energy to create glucose (perform photosynthesis)

• Decomposers - makes nutrients in dead organism available to other organisms (bacteria and fungi)

role of microbes in digestion

can cause infections and there are also microbes that help to digest food

examples of microbes in food and fermentation

mushrooms, yeast, seaweed, spirulina; fermentation of yeast, bacteria for cheese or kimchi

role of microbes in antibiotics and biotechnology

• production: microbes that create compounds that are able to kill other microbes

• vectors and enzymes

role of microbes in bioremediation

• Metabolize oil - clean up environment by degrading oil

why do we use microbes for biological research?

• size/structure

  • Relatively small and simple

• Large populations

  • Billions and trillions of cells

• Rapid growth rate

  • Double in 20min or fewer

• Research benefits

  • Vaccines 

  • Antibiotics

how do we get nitrogen?

We rely on bacteria to get our nitrogen, through nitrogen fixation, they can do the same thing with sulfur

microbes allow for the ___ in the ecosystem

recycling of nutrients

how are microbes used in agriculture?

• Microbes in cows break down cellulose to CO2 and methane

how are microbes used in biofuels?

• biofuels can be created with microbes, corn to ethanol

• microbes can be used to mine as well

• microbes ability to pull nitrogen from the atmosphere and convert it into another form is very important

microbes are important in?

• agriculture

• energy/environment

• food preservation and fermented foods or food additives

• biotechnology (GMOs or production of pharmaceuticals)

• Disease (new diseases or used as the treatment, cure, or preventative)

where can microbes be found?

• microorganisms are found nearly everywhere there is water and sometimes where there is not

• Found in hot springs, ice, and sea vents

• drilling cores

• undersea vents

why can microbes tolerate environmental stressors?

 because they have evolved to live in the environment where they are (environmental versatility)

How did linneaus classify organisms?

everything was classified as plants or animals

Who made and when were the classifications plants, animals, and protists

1866

Haeckel

How did Whittaker separate the kingdoms in 1959?

monera, protists, fungi, plantae, and animalia

How did Woose, Kandler, and Wheelis in 1990 make their classifications?

separated into bacteria and archaea (prokaryotes) and eukarya

What are the three domains of life based on?

DNA sequencing data, they were able to tell how organisms were related to each other

what do phylogenetic trees allow us to see?

how closely related organisms are

prokaryotes

• do not have a nucleus, DNA is freefloating

• include archaea and bacteria

what does it mean to for archaea to be environmental extremophiles?

they thrive in extreme environments

what size and shape can prokaryotes be?

• Between 0.5 - 2.0 micrometers, can be up to 60

  

eukaryotes and examples

• one domain; includes animals like us

  • “True nucleus” - DNA is found in a nucleus

• Insects (mosquitos or bees) and other arthropods (scorpions or spiders)

viruses

• Viruses are not cells, and they are not considered living because they cannot make their own energy

• Bacteriophage - viruses that infect bacteria

prions

• Very weird

• Not viruses, they are bad proteins that have the wrong shape

• Cause degenerative diseases in the brain, very rapid

what is the first line of defense? how does it fight infections?

• innate immune system

• they fight every infection the same way

What is the first line of defense’s physical factors made of?

the skin, mucous membranes, earwax, hair in nose, epiglottis, and peristalsis

what is the skin composed of? what helps it inhibit microbial growth?

• epidermis and dermis

• Shedding and dryness of skin inhibit microbial growth

epidermis

outer layer, consists of tightly packed cells, some contain keratin

dermis

inner portion, made of connective tissue

what are the mucous membranes made of?

mucus and ciliary escalators

mucus

viscous glycoproteins that trap microbes and prevent tracts from drying out

Ciliary escalator

• transports microbes trapped in mucus away from lungs

  • Goblet cells produce mucus

earwax

prevents microbes from entering ear

hair in nose

traps microbes

epiglottis

prevent food/microbes from entering lungs

what do peristalsis, defecation, vomiting, and diarrhea do?

all physically remove microbes from body

what are cleansing actions carried out by?

• Lacrimal apparatus

• Bodily fluids

what does the lacrimal apparatus do?

drains tears, washes eyes

what are bodily fluids functions?

• Saliva, urine, vaginal secretions, semen, nasal mucus

• Flow out and remove microbes and prevent colonization

what are the chemical factors of the first line of defense?

1. Sebum on skin: fungistatic fatty acid from perspiration

   1. Forms protective film and lowers pH (3-5)

2. Lysozyme destroys bacterial cell wall

   1. Perspiration, tears, saliva, urine, and tissue fluids

3. Low pH chemicals

   1. Gastric juice (1.2-3.0) - destroys microbes

   2. Vaginal secretions (3-5) - inhibits microbes

second line of defense

• has many functions

• Non-specific (present at birth) - involve specific types of cells

what happens after an injury?

• Infections form pockets of infections called abcesses

• Platelets in the blood rush to injury site to create a scab

what are some of the functions of the second line of defense?

• Infections form pockets of infections called abcesses

• Platelets in the blood rush to injury site to create a scab

• Phagocytosis - engulf pathogens and destroy them

• Secrete chemicals to cause inflammation

• Some cells interact to stimulate the third line of defense

what did Metchnikoff do? 1845-1916

• Won nobel prize

• Worked on role of white blood cells in fighting

• Discovered phagocytes in human blood

what is inflammation?

• redness, swelling, pain, and heat localized at the site of infection

• Attracts phagocytic cells to infected area

what does inflammation do? can it cause damage?

• Effective inflammatory response isolates and limits tissue damage, destroying damaged cells and pathogens

• Inflammation can result in considerable damage to healthy tissue if reaction becomes widespread

systemtic inflammatory reaction consequences

• septic shock

• uncontrollable fever

• death in up to 30% of individuals

what causes toxic shock syndrome?

• Certain bacteria, including staphylococcus aureus and streptococcus pyogenes produce “superantigens”

• these cause activation of 20% of T cells in the body, creating a cytokine storm

what is toxic shock syndrome associated with? how many cases a year? which famous person died from it?

• superabsorbent tampons

• Current numbers stand at 1-17 cases per 100,000 menstruating people per year

•  Caused death of very famous man in 1990 - creator of the muppets - Jim Henson

what is the third line of defense? what cells does it use?

• adaptive

• uses specific cells

• b cells and t cells

what does the third line of defense do?

• Reacts to specific proteins or other complex molecules on the pathogen’s cell surface

  • Antigens

  • Learns about every infection we’ve had

  • Reacts to specific parts of a molecule

characteristics of the third line of defense?

• Specificity of antigen-antibody is dependent on lymphocyte cell receptors interacting with individual pathogen

• Memory: subsequent exposures to the same antigen result in rapid production of large quantities of antigen-reactive T cells or antibodies

  • Like vaccines

• Tolerance: the acquired inability to make an adaptive immune response to one’s own antigens

  • Discrimination between foreign and host antigens - self and non-self

t cells activate a lot of things

b cells can produce antibodies to fight antigen

what are anitbodies made by? what are they made of? where are they found?

• made by B cells which become plasma cells that produce antibodies

• they are immunoglobulins or protein molecules

• found in serum, milk, and gastric secretions

IgG

• Located in tissue fluid and plasma

• Activates complement - punches holes in infected cells

• Defends against bacteria, viruses, and toxins

• Protects fetus and newborn - found in placenta or breast milk

IgA

• Located in secretions

• Defends against bacteria and viruses

IgM

• Located in plasma

• Reacts with naturally occurring antigens on RBC’s following certain blood trasnfusions

• Activates complements, which destroys blood cells

IgD

• Located on surface of most B lymphocytes

• Plays a role in B cell activation

IgE

• Located in secretions

• Promotes inflammation and allergic reactions

what are the three steps of antibody production?

• exposure to antigen and secretion of antigen-specific antibody

• antigen-stimulated B cells multiply and differentiate into plasma and memory cells (primary antibody response)

• Memory B cells generated may live for years and quickly transform into antibody-secreting cells (secondary antibody response)

antibody effects

Agglutination

• cross-bridges of antigen and antibody, complex forms

Complement mediated effects

• Opsonization

• Lysis

Neutralization

• Toxins and viruses, prevents from binding to cell

What are the T cell types?

• Helper T cells: stimulate immune response, activate t cells, b cells, and mmacrophages

• Delayed hypersensitivity T cells - allergies

• Cytotoxic T cells - death of infected cell

• Memory t cells: remember infection and can turn into cell to fight it

Active vs passive immunity

active : patient made antibodies

Passive: someone else passed on antibodies

Not everyone has had artificial passive

what are vaccines? what are they made of?

Designed to provide the first exposure to disease-causing organisms without having the risk of disease

• Made with dead or attenuated,weakened pathogen, or with pathogen fragments

what is herd immunity? how does it work?

• is the resistance of a group to infection due to immunity of a high proportion of the members of the group

• Immunized people protect non-immunized people because the pathogen cannot be passed on and the cycle of infectivity is broken

how is health measured from prehistoric remains?

• harris lines

• wilson bands

• enamel hypoplasia

what are harris lines? what do they indicate?

•  Any of various dense transverse lines observed in radiographs of long bones, representing bone regrowth after temporary cessation of longitudinal growth

  • Indicates during childhood when bones were growing, shows a period of malnutrition or sickness

what are wilson bands

changes in tooth enamel due to poor diet

what is enamel hypoplasia? what does it indicate?

• irregularities in tooth enamel

  • Indicates periods of malnutrition

characteristics of early man?

• gathering

• hunting

• agriculture - 10,000 BP

  • crops

  • fishing

  • domestication of animals

  • settlements

animal domestication during the neolithic/agricultural revolution. how did it cause more disease?

• Livestock, pets (livestock- cattle, work - horses, pets - dogs)

• Diseases shared with animals - people began living with animals and experiencing their diseases (ectoparasites - fleas and ticks)

environmental disruption during the neolithic/agricultural revolution.

• Living in groups (settlements)

• Tons of people were living in close proximity to each other and interacting every day

problems with city life

• Garbage

• Social change - rules

• Changes in work

• Crowds

• Fire

• Disease

what was the pharaoh’s plague?

• bloody urine

  • Caused by Schistosomiasis - blood flukes - worms that live in blood

what was suspected to be in athens?

typhoid or typhus

Rome diseases

• Roman fever = Malaria

• Antonine plague = smallpox?

• Cyprian plague = Smallpox or measles? Ergot poisoning? - ergot is a fungus that infects barley and millet

• Justinian plague = Bubonic plague

what is schistosomiasis? how do the worms get into the body?

• parasitic disease caused by trematode flatworms of the genus Schistosoma 

• Larval forms of the parasites penetrate the skin of people in the water

urinary schistosomiasis

there is progressive damage to the bladder, ureters and kidneys

intestinal schistosomiasis

there is progressive enlargement of the liver and spleen, intestinal damage, and hypertension of the abdominal blood vessels (high blood pressure)

ancient evidence of schistosomiasis

• an analysis of mummified skin revealed traces of proteins belonging to S. mansoni - the first proof that ancient Nubians (1,500 BP), or any ancient civilization were affected by schistosomiasis - found proteins in the skin

how is typhoid passed? what are the symptoms? how long does it last? who is most susceptible?

• Bacteria passed in feces

• Diarrhea, fever, and abdominal cramps 12 to 72 hours after infection

• Illness usually lasts 4 to 7 days, and most persons recover without treatment

• Elderly, infants, and those with impaired immune systems more likely to have severe illness

when did the plague of athens break out? what facilitated it? what disease was it suspected to be?

• broke out in Greece during the Peloponnesian War in 430 BC

• Inhabitants of Athens retreated behind the city-state’s walls for protection from Sparta

• Cramped quarters inevitably became a breeding ground for the disease

• typhus or typhoid

is typhoid in the US? what did Typhoid Mary do?

• Does exist, but isn’t very common due to good sanitation

• Typhoid Mary killed about 1,300 people due to spreading disease to families that she worked for

• She was quarantined for the rest of her life because she refused to take her gallbladder out

what plagues were in the ancient world?

• Smallpox - in the Roman world and everywhere - viral

• Shigella - bacteria

• Malaria - protozoal

• Measles - viral

• Cholera - bacterial

• Dengue - viral

• Plague - Justinian - led to the middle ages - bacterial

Why is it hard to know what the cause of ancient disease was?

• Ancient people did not record the information about the disease

• Ancient people could not identify the disease the same way we do

• We cannot isolate bacteria from people who have been dead for thousands of years

what time period was the Middle Ages?

• Talking about Fall of Roman Empire to the fall of Constantinople, around 2000 years

• Cities were becoming densely packed

What were the 3 new diseases of the middle ages?

• Leprosy (ancient) - transmitted by direct contact

• Tuberculosis - transmitted by inhaling bacteria

• Sweating sickness - high fever, sweating, and high mortality rate (no real definition)

where was leprosy found? what does it do? what are the complications? how is it transmitted in the US?

• was in egypt around 3,500 BP

• Actually not very contagious

• Leads to nerve damage and death of extremeties

• Disease frightened people

  • Many sent to live in leper colonies - isolated there for rest of their life

  • Including those with other diseases

• Slow growing bacteria makes treatment difficult

• Similar to tuberculosis

• Extended antibiotic treatment

• In US, transmitted by armadillos

ancient plagues (3)

• Malaria - transmitted by mosquitos

• Smallpox - relatively high mortality rate

• Bubonic - caused by yersinia pestis, can get it from camping near yosemite

what were the 8 ancient treatments

• bathing in blood

• blood letting

• mercury/arsenic

• animal dung

• moldy bread

• therapeutic stink

• mice

• venom

bathing in blood

• Blood of children and virgins was best

• Used as a therapy for leprosy until 1790

blood letting

• Balanced the “humors” (bad bodily fluids)

• Used leeches 

• Used for many diseases, including plague

• George washington was treated this way before his death

mercury/arsenic

• Used to treat infectious diseases, including syphilis, until the early 20th century

• Also made people crazy/killed them

animal dung

• Egyptians used it for diseases and infections

• Some antimicrobial properties, could also cause tetanus

moldy bread

• Egyptians used to disinfect cuts

• Many microbes are used to create antibiotics so they somewhat act as antibiotics

Therapeutic stink (aka farts in a jar)

• Plague thought to be caused by bad vapors

• Use like to defeat like

• Thought they could balance the smell

mice

• Egyptians would make mouse paste for toothaches

• Elizabethan england - cut a mouse in half to cure warts

• Also used to treat whooping cough, smallpox, measles, and bed-wetting