Microbiology

Microbiology is the study of all living organisms that are too small to be visible with the naked eye

0.1 mm smallest thing the naked human eye can see

Sneezes and coughs are referred to as droplet transmission

Particles om the air are referred to as airborne transmission

Covid has a single strand of RNA in the genome

Influenza has 8 strands of RNA in the genome

Ames strain is the worst form of anthrax disease

Anthrax bacterium has the ability to make spores and has a rod shaped look

Ecoli O157:H7 (enterohemorrhage E.coli) damages the lining of the intestinal walls

A strain is a genetic variant, subtype, or culture of a microorganism

Strains ae made up of organisms that belong to the same species but have different characteristics

E coli can be found in cow intestines but does not affect them, however, it can affect humans

These toxins found in e coli affect our red blood cells

Nosocomial infections are hospital acquired diseases

MRSA (Methicillin-resistant staphylococcus aureus) is a staphylococcus bacteria that has become resistant to many antibiotics, can be gained through a hospital or community associated

Self assessment

how many infectious diseases you learned so far (Lecture 1 and 2)? List them out and their causative organism (its scientific name, and what type of microorganism: whether it is a bacterium, fungi, yeast, or a virus

Influenza (Alphainfluenzavirus influenzae) is a respiratory virus

Covid (SARS-Cov-2) is a virus

tuberculosis (Mycobacterium tuberculosis) is a bacterirum

Anthrax (Bacillus anthracis) is a bacterium

E coli (Escherichia coli) is a bacterium

MRSA (Staphylococcus aureus) is a bacterium

Carbohydrates have three types

Monosaccharides (monomers) and Disaccharides (dimers) are made up of sugars. Monomers are made up of one units and dimers made up of two

Polysaccharides (polymers) are made up of many units

glucose and fructose are made up of two monosaccharides sucrose is made up of two

Beta 1-4 in cullulose (the first carbon combined with the fourth)

Alpha 1-4 in starch

Lipids are made of fats / triglycerides

They contain ester bonds

Phospholipids- the head is hydrophobic and the body is hydrophilic

Steroids consists of cholesterol and ergosterol

Proteins are made up of amino acids, they always have a central carbon atom made up of four groups, a carboxyl group, amino group, and a hydrogen bond, they also have a side chain (basically the reason why their are different amino acids)

Peptide bonds

Nucleotides

There are two types of pentose sugars, deoxyribose nucleic acid (DNA) and ribonucleic acid (RNA)

Nitrogenous bases

DNA has the double helix structure and does not contain uracil

RNA is single stranded

ATP is the universal energy molecule

It breaks down the high energy bonds between the phosphates releases energy that can be used for cellular functions

Self assessment:

1. What is an enzyme?

2. Why are enzymes required for an organism?

3. What is metabolism?

4. What is catabolism?

5. What is anabolism?

Domain - most broad

Kingdom

Phylum

Class

Order

Family

Genus

Species - most specific

Homo Sapiens (humans)

Genus species

Whenever written underline both, whenever typed italicized both!

Genus names are always capitalized, species are always lowercase!!

Eukaryote vs prokaryote

Has nucleus vs doesnt

Bacteria can take up three different shapes: Bacillus(rod), Coccus(sphere), and spirillus (spiral)

Bacteria are colorless, but their cell wall can be colored using dye molecules. This method is called staining.

The dyes are positively charged and are attracted to the negative charges of the cell wall.

Gram positive is when they have a thick peptidoglycan layer

Gram negative the peptidoglycan layer is very thin

Ziel Neelson acid fast stain

Disease is like tug of war, pathogens vs the human host

The black death (bubonic plague, Yersinia pestis) was caused by a flea bite and is called a vector bond disease

Pathogens are any organism that can infect humans and cause illness

A host is an organism that supports the growth of a pathogen or parasite

Pathogenicity is the capacity to produce a disease

Virulence is the intensity of the disease produced vary among different microbial species

Non-pathogenic bacteria vs pathogenic bactea ria, the difference is the virulence

Normal flora (resident flora) refers to the microorganisms that live in or on the body that are fine and help the body, they maintain a postive or mutualistic host microbe relationship (ecoli in a specific person)

Transient flora is the microorganisms that are temporarily harbored on the superficial surface of the body (they can be washed away)

Primary pathogens cause disease in healthy individuals (plague, cold, mumps, flu, etc)

They evolve their mechanisms that allow them to overcome host defense mechanisms

Opportunistic pathogens can cause disease in the immunocompromised host (ecolu staphyloccocus aureus, etc)

For a bacteria to be pathogenic they must do five things: get in, stay in, avoid the defense mechanism, damage the host and spread the infection, and exit and find another host to infect

Virulence factors of pathogens are encoded by genes found in the chromosome and plasmids

Quorum sensing is a form of cell to cell communication that allows bacteria to monitor their population density and coordinate collective behavior

Bacteria releases autoinducers (signaling molecules) which accumulate and trigger a group-wide response once a threshold concentration is reached, synchronizing activities like biofilm formation, bioluminescence, and virulence factor production

Biofilms are communities