microbiology exam #2

Coenzyme- organic cofactor

(ex: B vitamins)

Cofactor- required by SOME enzymes

(ex: Mg++)

Bacteriophage always lyse the cells

(host cell always dies) Lyse means cell burst open

Enzyme Temperature

-(increase temp. Causes reaction rate to increase) -35-40 is optimally active in these temperatures -If go higher causes it to fall apart

Virus specificity

-Animal viruses (Can't affect anything but animal) -Plant viruses -Bacterial viruses (bacteriophages or phages)

Enzymes

-Are proteins, but not all proteins are enzymes -Catalyze (speeding up) SPONTANEOUS reactions only (happens on its own)

Why isn't oxygen O2 a nutrient?

-Bc it is not broken down for energy or used by biosynthesis -O2 is simply a final electron acceptor

Model of prion disease

-Brain cell producing normal protein -Prion the same protein but slightly altered (scrapie) -Difference in normal protein and altered is how it is folded -Interacts with normal protein and causes it to mishape so becomes prion

Bacterial growth

-Cannot run out of space -Can run out of nutrients -Stationary phase

Energy

-Energy currency of the cell is ATP (not stored as ATP) -Has approx. twice the energy of ATP

Prion (mad cow disease)

-Found in cows -Cows eating sheep with scrapie -(bovine spongiform encephaopathy)

prion kuru

-Found in papillon new guinea -When relative dies, you eat them

prion Creutzfeld-jakob disease

-Human variant of mad cow disease -Can develop this spontaneously -Eating a cow with mad cow disease or passed genetically

Lysogenic conversion

-In general, viruses do not produce toxins -Prophage for DNA is coding something different 1)Creates botulinum toxin 2)Scarlet fever toxin 3)Diphtheria toxin all three created if lysogenized to produce the toxins

Metabolism

-Inside of the cell Sum of all chemical reactions in a cell between (1,000 and 2,000) -Catabolism-break down nutrients (Generate energy from nutrients) -Anabolism-build up (Or biosynthesis)

Chemoatutotrophs

-Live deep down in ear and ocean -Usually anerobic -Greatest number of organisms in our planet

Growth

-Measure growth by increases in numbers -Conditions: temperature and PH

Why aren't viruses living

-Not cellular -Can only replicated inside of a host cell -No ATP-generating system (energy of cell) -No ribosomes -Contain only one nucleic acid No metabolism

Chemoheterotrophs

-O2 all animals -And us -Get resource from organic compounds

Viruses

-Obligate intracellular parasites -Must exist within a living cell, can't do anything outside of a cell -Non-living -Purpose is to replicate

T-even bacteriophage

-Only affect e-coli -Lytic cycle

What are viruses made of

-Protein coat-capsid -Made of capsomeres -Protects the nucleic acid -Responsible for shape -Nucleic acid Ds DNA (herpes) Ss DNA (B19-fifth disease) Ds RNA (rotavirus) Ss RNA (rhinovirus, flu virus, SARS CoV-2)

Prions

-Proteinaceous infectious particle -End up in neuron tissue Usually get them by eating (usually brain matter) -Prion diseases (no cure) (all found in the brain matter of either animal/person) (caused by infectious proteins)

Protein nutrient for a cell

-Proteins are NOT nutrients for cell (too big) -Their breakdown products, amino acids, are the nutrients

Fermentation side

-Pyruvic acid reduced by electrons created in respiration NADH -End up with fermentation products

N2 Nitrogen Source

-Some microorganisms can covert atmospheric molecular nitrogen into organic nitrogen which can be used by many organisms -Called Nitrogen Fixation

How do we control viral infections

-Vaccines (best way to prevent viral infection) -Anti-virals (chemicals for viruses)

Final electron acceptor

-Where electrons end up 1) O2 aerobic resportation 2) Only reason we breathe in oxygen is bc final electron acceptor 3) NO3- and SO4^2- anaerobic respiration 4) Organic compound (fermentation)

some viruses have

-have an envelope -To enter lipid bilayer fuses with cell -Attach to host cell -Have spikes -Covid vaccine is an envelope virus

enzyme example

-lactose (milk sugar, disacharide) = glucose+galactose -At equilibrium 1% lactose and glucose+galactose 99% -Lactose dissolved in water will go through equilibrium in 1 year -If added an enzyme will take minutes

Lytic cycle

1) attachment 2) penetration (injects nucleic acid) 3) biosynthesis 4) maturation (virsuses organize) 5) new viruses released

Respiratrion side

1) kreb cycle 2) All carbon in glucose turned to pyruvic acid will be oxidized to carbon dioxide 3) NADH and FADH2 will be produced with high electrons 4) ATP also produced 5) If pyruvic acid can't go through respiration route it will die 6) Streptococus missing an enzyme in the kreb cycle so can't do any respiration Only can do fermentation

Micrortanism in response to temperature

1) mesophiles 2)thermophiles 3)hyperthermophiles 4)psychotrophs 5)psychophiles

Lysogenic cycle of bateriophage (lamda) in e.coli (lytic cycle)

1) phage attaches to cost cell and injects DNA 2) DNA circulizes 3) New DNA 4) cell lyses and releases phage

Pathway of glycolysis

1) sugar aka glucose (6 carbon compounds) 2) broken down into pyruvic acid -Oxidized so removed electrons -Glucose was catabolized (broken down)

Viral replication

1) virus particle attaches to host cell 2) virus must enter and uncoat 3) nucluic acid enters nucleus and creates RNA (biosynthesis) 4) maturation 5) form new viruses and infect other cells (may or may not kill host cell) (ebola most dangerous)

Methods of ATP Generation

1. Substrate-level phosphorylation (Phosphate donated from an organic compound to ADP to make ATP Ex: 3 carbon organic phosphate (CCCP) + ADP = (CCC) + ATP) 2. Oxidative phosphorylation (Uses an electron transport chain) 3. Photophosphorylation (Uses an electron transport chain)

Capsomeres A) Are the protein units that make up the capsid. B) Are building blocks for the viral nucleic acid. C) Are required to make the viral envelope. D) Are only found in lysogenized cells. E) None of the above.

A

What are the products of glycolosis

ATP, pyruic acid, NADH

Budding, when it refers to viruses, has to do with A) Replication of non-enveloped viruses. B) Replication of enveloped viruses. C) Replication of prophages. D) Replication of bacteriophages. E) Replication of the host bacterial cell.

B

Viruses A)Have an ultimate purpose of killing the host organism. B)Simply want to replicate. C)Produce toxins inside of cells. D)Produce toxins outside of cells. E)All of the above.

B

Which of the following statements about anaerobic respiration is false A) Generates ATP B) Involves the reduction of an organic final electron acceptor C) Yields lower amounts of ATP when compared to aerobic respiration D) Complete Kreb's cycle is utilized E) Generates carbon dioxide

B) Involves the reduction of an organic final electron acceptor (aka fermentation)

Virus particles form bud

Budding different than with yeast

A strictly fermentative bacterium produces energy

By glycolsis only (ex: streptococcus)

The ultimate oxidation product of glucose is

CO2

All viruses contain

Capsids

Which describes a microorganism that can use the inorganic compound hydrogen sulfide H2S as an energy source

Chemoautotroph (inorganic sources of energy, possibly largest group of organism on planet)

If you see a deer staggering in the woods, don't kill it and eat it bc it might have

Chronic wasting disease

Viruses are not considered living because A) All viruses are just too small. B) They carry out metabolism only within living cells. C) They only produce ATP within living cells. D) They have no ribosomes. All of the above. E) All of the above

D

Bacteria goes through binary fission

DNA replicates

Measurement of Growth

Direct microscopic count Dilution and plating Turbidity measurement

Nonenvolvope virus

Enters through endocytosis

Wild type E. coli does not require as a nutrient

Essential metabolites

What are the most important products of fermentation

Fermentation end products and NAD+

(Prion) Chronic Wasting Disease

Found in deer

Chemotroph

Get energy from chemicals

Which contains the most amount of energy

Glucose

biological oxidation what is removed from the donar molecule

Hydrogen atoms

The breakdown of lactose into glucose and galactose

Is a spontaneous reaction (Does not require an enzyme)

Clostridium botulinum produces a toxin bc

It contains a prophage

Unlike lytic virus, lysogenic viruses do not

Lyse the host cell immediately

Obligate intracellular

Must exist within a living cell, can't do anything outside of a cell

Viroid

Naked RNA Potato spindle tuber disease

Hyperthermophiles

Organisms that grow in extremely high temperatures (90 degrees C) ex: hot springs

Chemiosmosis is an essential part of both photophoylation and which other type of phosphorylation

Oxidative

Organisms that love living in the refrigerator are typical in which category

Psychrophiles

NAD+ becoming NADH is an

Reduction

Which method of counting bacteria does not count the anaerobes

Spread plate method

ATP production in Glycolysis occurs via

Substrate-level phosphorylation

Building blocks for biosynthesis come from

The core pathways (glycolysis and the kreb cycle)

Which of the following is the best definition of fermentation

The partial oxidation of glucose with organic molecules serving as electron acceptors

The best way to prevent a viral infection is

Vaccinations

Oncogenic Virus

Virus that causes cancer (onco=cancer)

In the presence of oxygen

all organisms produce superoxide (O2-). this is deadly Organisms that survive in the presence of oxygen produce superoxide dismutase

Catabolism

breaking down

Anabolism

build up

faculative anaerobic bacteria

can live with or without oxygen

organic=

carbon with hydrogen attached to it

PEP is not the energy

currency because it costs too much energy to make it (has to have an intermediate energy level)

virus size

does not matter with how dangerous disease is ex: ebola

yeast produce

ethanol = alchol

T/F Organisms that are only on fermentation side are at a disadvantage

false

Mesophiles

grow at moderate temperatures, grow on body

Psychotrophs

grow in room temp.

Thermophiles

heat loving

Streptococcus produces

lactic acid

Psychophiles

lives in cold enviroment

Oxidation

loss of electrons

Optical density

measures how well a medium can transmit light -Turbidity measures optical density -spectrophometer

Phototrophs

obtain energy from light

Photohetertrophs

organic molecules obtained from the enviornment as the source of carbon for growth and other vital functions

All viruses have

protien coats and one nucleic acid

Viruses purpose

replicate

nutrition

required by cell 1) carbon source 2) Nitrogen source 3) certain inorganic ions 4) essential metabolites 5) water

Aerobic

requires oxygen

Prion scrapie

sheep

Substrate Concentration Activity increases with

substrate concentration (not enzyme concentration)

Factors that influence enzyme activity

temperature, pH, substrate concentration

Photoautrophs

use light energy to make organic food -Annoxygenic -Plants

Anaerobic

without oxygen