Micro Test 1

deals with living things too small to be seen without a microscope

exist as single cells or clumps of cells

all humans, plants, and animals

bacteria and Archaea

not a cell--live inside a eukaryotic or prokaryotic cell--no metabolism outside the host cell
Refer to as "viral agents"

1600s, invented the microscope and found microbes
most of human existence had no knowledge of microorganisms

invented what we now call pasteurization -> increases shelf life doesn't kill all microorganisms, can't kill in spore state
disproved spontaneous regeneration w bacteria
wanted to prevent wine spoiling -> bacteria metabolizes & makes wine go bad through producing acids -> creating vinegar

a process of mild heating to kill susceptible spoilage microorganisms and vegetative pathogens, does not kill spores
approx 158 F or 70 C

bacteria metabolically active

bacteria not metabolically active

thought that microorganisms (bacteria) can cause specific diseases
1800s people began to think microbes make people sick & ^ proved it

clearly showed women in maternity ward of hospitals became infected more often than if delivered by midwife at home
Dr. go from autopsy to delivery without washing hands

even today serves as a cornerstone of microbiology and serves as a set of criteria that must be met before one can say a specific disease is caused by a specific microorganism

1) The microbe is found in every case of the disease (and absent from healthy individuals)
2) The microbe must be isolated from an infected individual and grown in a pure culture
3) Inoculate a healthy host and observe the same resultant diseases
4) Isolate the same microbe from diseased host

Late 1800s, applied germ concept (that microbes can cause disease) to surgery
used chemical disinfection in treatment of surgical instruments -> greatly reduced the number of post-surgical wound infections

concept of chemotherapeutic agents -> chemical that has therapeutic value
neurological syphilis -> arsenic (found by Paul Elrich)

sulfa drugs (contains sulfur) -> petroleum industry
inhibition of folic acid creation thus prevents bacteria growth

common mold Penicillium (often green color) -> penicillin (antibiotic)
1st widespread use of antibiotics -> D-Day

a metabolite produced by one microorganism that inhibits a specific metabolic pathway in another microorganism

1) Cell wall synthesis
2) Protein synthesis
3) DNA synthesis
4) Inhibition of metabolism (folic acid synthesis)
5) Inhibition of cytoplasmic membrane function

penicillin antibiotic (type of penicillin)

includes all pathogenic protozoa such as malaria and trichomonas, Giardia, and all fungi and algae
more difficult to satisfactorily treat bc more similar to human cells than bacteria

nucleus--contain chromosomes and DNA is wrapped around histone proteins
Mitochondria--has its own DNA, replicates inside the cell, the more energy needed the more mitochondria the cell has
can do interesting genetic studies on mitochondria DNA and also is used in forensic analysis

all are prokaryotic cell
1) DNA not enclosed in a nucleus-bacteria lack a defined cell nucleus
2) DNA not wrapped around histone proteins
3) DNA is circular not linear--all have a single circular chromosome
4) No mitochondria
ALMOST ALWAYS have a cell wall composed of peptidoglycan. Important--we don't make cell walls

not all bacteria have
promote attachment (thus promote colonization & development)
and antibiotic resistance
promote formation of biofilms which are very difficult to treat with antibiotics
also sometimes used in vaccine preparation

movement .00085 mph--is fast relative to the size also can serve in attachment

small hair like structures promote attachment
bacteria have a hard time sticking to teeth
streptococcus mutans -> causes cavties/ bacteria to stick to your teeth
neisseria gonorrhoea = sticks to genital tract

promote conjugation and can promote attachment
help bacteria stick to other DNA

bacteria can exchange DNA with other bacteria

found only in Gram negative bacteria
a molecule extremely important to human health
toxic to animals especially humans
apart of the structure & sheds like hair
a pyrogenic compound (fever)
can cause what is known as septic shock--high fever, reduced blood flow to vital organs, elevated respiratory rate, etc. (blood vessels constrict)
Anything that goes into people MUST be tested for LPS--IV, medical devices, etc./ non-pyrogenic

synthesized inside bacteria & released into the environment
not apart of the structure

perform Limulus amebocyte assay--use fluid from horseshoe crab
used to show presence of LPS--if fluid goes from liquid to gel state LPS is present--by doing dilutions can determine how much LPS is present
cannot destroy LPS once in the body

a polymer composed of peptidoglycan

composed of sugar derivatives and amino acids

a thick layer of peptidoglycan and teichoic acid

a much thinner layer of peptidoglycan

1) Mycoplasma pneumonia
2) Chlamydia pneumonia
3) Chlamydia trachomatis

damage to bacteria cell wall is extremely important concept in treatment of bacterial infections
antibiotics -> inhibit peptidoglycan synthesis (humans don't have)

surrounds cell
2 layered structure composed mainly of lipids & proteins with protein channels
If broken cell may die--contents flow out
bacteria most often have a cell wall to aid in holding cell together
eukaryotic human cells do not so if broken contents may flow out

philic - likes water
phobic - dislikes water
bilayer (two layers)

substance chemically altered in passage across the membrane, usually put a phosphate on it
defense mechanism of cells
when happens, no longer the same drug & you give an overwhelming amount to overcome the cells ability to change it

enters cell unchanged

generally a single circular chromosome, not wrapped around histone proteins, 500 times longer than the cell
supercoiled (twisted rubber band)

function like in eukaryotic cells but differ in size--can be site of antibiotic action

smaller circular extrachromosomal pieces of DNA--confer traits such as antibiotic resistance and toxin production--can be transferred by a process called conjugation

hardiest of all life forms resistant to extreme heat, drying, freezing, radiation, chemicals that easily kill vegetative cells
formed in unfavorable environmental conditions
will stay in spore state until comes in contact w/ good environmental conditions
could stay in spore state for thousands of years until activated

1) Clostridium tetani
2) Clostridium botulinum
3) Bacillus anthracis

an exotoxin--prevents muscle relaxation--often first group of muscles affected are located in the jaw--so the name "lockjaw"
can only germinate in anaerobic conditions

an exotoxin--causes flaccid type paralysis--cannot contract muscles
SIDS--could be grown from children's feces & causes the diaphragm not to contract
honey--could disrupt the natural flora of stomach & lead to SIDS in children
Botox--relaxes the muscles & needed every 3-4 months

antrax (carried by some animals)--used as chemical warfare/ biological weapon
3 weeks after 9/11 someone put anthrax spores in mail
meets Koch's Postulates
hot zone the anthrax attacks

mRN--viral messenger RNA coded with same phospholipids that compose our cell membranes & put it around the vaccine
body has the antibodies from the mRNA vaccine to make spike proteins to de-spike the virus

potentially kills viruses

yields energy
requires enzymes
can be respiration (aerobic & anaerobic) or fermentation
primarily sugars

uses energy to snythesize molecules
requires enzymes
uses energy to make building blocks: amino acids, sugars, nucleotides (building blocks of DNA & RNA) fatty acids--all have cells

proteins that increase the rate of a chemical reaction without becoming part of the products or being consumed in the reaction
biological catalyst -> something that speeds up a reaction w/o itself being changed
a protein whose name ends in ase (protease, amalyase)
specifically interacts w/ a specific molecule called the substrate to change it in some way

an effective way to control bacteria growth, viral growth, cancer growth
look for unique enzymes to selectively inhibit
problem with cancer--no unique enzymes to selectively inhibit

eukaryotic cell-similar to our cells-few enzymes to specifically inhibit -> harder to find inhibitors bc very similar to us

use host cell enzymes--few if any unique enzymes to selectively inhibit

1) Tamiflu--neuraminidase inhibitor
2) Remdesivir--target viral RNA polymerase
3) Paxlovid--3dL protease inhibition

Competitive inhibition--if the inhibitor interacts with the active site the substrate cannot interact with the active site (Sulfadrugs)
Noncompetitive inhibition--if inhibitor interacts with anything other than the substratre (cyanide has enzymes oxidase)

enzyme inhibitor

needed in order for enzymes to properly function
Metals--iron, copper, zinc, selenium, etc.
Vitamins--which is why vitamis are important and may be required for growth factors
activity is specific and also influenced by temperature (98.7F/37C), pH, substrate concentration

a series of enzymatically (hundreds) catalyzed chemical reactions

1) Glycolysis
2) Krebs cycle
3) Electron transport chain
This occurs in respiration of glucose

process of breakdown of sugars to pyruvate

main products are NADH and FADH2

majority of energy is produced

transfer of energy from nutrients is by removal of electrons--this usually involves the removal of hydrogen--called dehydrogenation

nictoinamide adenin dinucleotide-NAD
flavin adenine dinucleotide-FAD

Beta oxidation

broken into AA to pass through cell membrane

carbohydrates -> favorite source of energy, broken down into polysaccharides, glucose most common
membranes of the mitochondria -> where electron transport chain is
bacteria -> cell membrane -> electron transport chain is

uses oxygen as the terminal electron acceptor in a membrane bound pathway for ATP generation
humans, bacteria, animals

uses compounds other than oxygen as the terminal electron acceptor in a membrane bound pathway for ATP synthesis
anaerobic bacteria do not grow as fast -> produces odors, most of intestinal bacteria are anaerobic, causes a variety of diseases in humans
some bacteria can multiply ONLY under anaerobic conditions

external

some cells perform catabolism of substrates by a mechanism other than respirations
ATP generated primarily during glycolysis
does not require or use oxygen--all pathways are anaerobic
oxygen may be present but is not used
not an efficient means of energy production

1) acids & doesn't enter electron trans. chain -> lactic acid, acetone, citric acid
2) acetaldehyde -> ethanol (alcohol) goes straight to alcohol so has many carbohydrates

peridontal disease -> likely caused by a variety of anaerobic bacteria
tetanus -> clostridium tetani
clostridium botulinum
clostridium difficile (cdiff)