Bacteria & Introduction Flashcards
Microbes
Organisms too small to be seen with naked eye
Microbiology
The study of microbes
2 concepts of microscopy
Magnification and Resolution
Magnification
increase in size of an object from its original size
Resolution
clarity; minimum distance between 2 objects
Microbes
organisms too small to be seen with naked eye
Example of Microbes
bacteria; fungi, algae; protozoa; helminths; viruses, non-living
What are Helminths?
parasitic worms; like tapeworms (platyhelminths)
Virus
non-living microbes made up of genome (DNA or RNA) and protein molecule
Fungi
eukaryotic microbes; mushroom (macro), yeast, mold, (micro)
Bacteria
prokaryotic microbes
Algae
eukaryotic microbes; plant-like organisms
Protozoa
single-celled eukaryotic microbes
Prokaryote
organism without a nucleus and unorganized organelles (not membrane-bound); have cell wall made of peptidoglycan; includes Archae and Bacteria
Peptidoglycan
polysaccharide composed of NAM and NAG that make up bacterial cell wall
How do you kill bacteria?
have to kill NAM and NAG to kill cell wall (made of peptidoglycan), which kills the bacteria
Eukaryote
organism with a nucleus and organized organelles (membrane-bound); some have cell wall; includes Protista (Protozoa), Plantae (Algea), Fungi, Animalia (Helminths)
What are Plantae cell wall composed of?
cellulose
What are Fungi cell wall composed of?
chitin
What are Animalia cell wall composed of?
they do not have a cell wall
Germ theory
microbes are the causal agents of disease; life begets life
Taxonomic Hierarchy (List the order of the hierarchy)
system of classification from domain to species; Domain -> Kingdom -> Phylum (Division - Plants) -> Class -> Order -> Family -> Genus -> Species
Binomial Nomenclature
system of naming organisms with two names: Genus and species
Taxonomy
the classification, naming, and identification of organisms
Cytoplasm
cellular matrix (cytoskeleton) containing cytosol and organelles
What is an unfavorable environment for bacteria?
lack of nutrients, lack of moisture
Capsule. What is it composed of?
structure made of polysaccharide & polypeptide on the cell wall of some prokaryotes
Glycocalyx
capsule and slime layer (on capsule) surrounding the cell wall of bacteria
Flagella
long, whip-like appendages used for motility and sensory perception
Fimbriae
AKA Cilia; short, hair-like appendages used for movement or sensing
What are the bacteria cell appendages?
flagella, sex pili, fimbriae (cilia)
Sex Pili Explanation
No male or female bacteria; over time one may act as male (donor cell), protruding sex pili, and transfer genetic material to other, which will act as female (recipient cell); plasmid (DNA molecule) is transferred
Do bacterial cells have outer membrane?
some do, dome don’t. They are harder to kill if they have them
Mesosome
where the cell membrane (beneath the cell wall) of bacterial cells “falls in”
Periplasmic space
space between cell wall and cell membrane; contains chemical that can neutralize other chemicals; not all bacteria have them
Nucleoid
region in prokaryotic cell (bacteria) containing genetic material
Ribosomes
cellular structures responsible for protein synthesis
Prokaryotic Cell Ribosomal Subunits
small unit = 30s (aminoglycosides) destroy
large unit = 50s (Microlytes) destroy
ex: Clarithromycin & Azitromycin
Together = 70s
Bacterial Granules
storage for nutrients
Microbistatic
inhibitory drugs that slow down bacterial growth
Microbicide
destructive drugs that kill bacteria
Which type of drug is preferred for bacteria with outer membranes?
Microbistatic, because if try to kill bacteria, toxic outer membranes can release toxins into body
How do bacteria know there is food in the environment?
flagella
The 2 forms of Bacteria
Endospores; Vegetative cells
Endospore
form of bacteria; can survive for 250 million years; cannot kill them using drugs, heat, or radiation; will grow and germinate when get to where environment is favorable
What chemical does bacteria secrete to form endospore?
Calcium Dipicolinic Acid
Vegetative Cells
AKA Vegetative Pathogen; infectious bacteria; can be killed using drugs, heat, or radiation
Sterilization
complete and total elimination of all micro forms
Types of Spores
subterminal spore; terminal spore; central spore; lateral spore
Subterminal Spore
doesn’t go all the way to the top
Terminal spore
goes all the way to the top and end
Central spore
spore is only in center
Lateral spore
spore is on the side
Types of flagella
monotrichous; lophotricous; amphitrichous; peritrichous; atrichous
Monotrichous
one flagella
lophotrichous
Bunch of flagella on one end
Amphitrichous
flagella on both ends (one or multiple)
Peritrichous
flagella all over the place
Atrichous
without flagella
Culture
the growing of live bacteria
The Six I’s of Culturing
Inoculate; Incubate (@37 C); Isolate; Inspect; Information Gathering; Identification
Thermophilic
bacteria that like extreme heat
Psychrophiles
bacteria that like extreme cold
Halophiles
bacteria that like high salt concentration
Mesophiles
bacteria that thrive in human body temps
Physical classification of media (List & Ex)
liquid: broth
solid: agar plate
semi-sold: agar slant
Chemical classification of media (List & Define)
synthetic: artificial, ratio is known
non-synthetic: natural, ratio is unknown
semi-synthetic: both natural and artificial, ratio is unknown
Functional classification of media (List)
general purpose; selective; differential; enriched; reducing
General purpose media
grow wide range of bacteria
Examples of General Purpose Media
Ex: TSA (Tryptocase Soy Agar)
Ex: NA (Nutrient Agar)
Selective media
selectively encourage growth of 1 species, while discouraging/inhibiting growth of others
Examples of Selective Media
Ex: MSA (Mannitol Salt Agar)
Ex: MacConkey
What is MSA (Mannitol Salt Agar)?
a selective media used to grow Staph aureus by showing yellow gold during bacterial test, confirming staph infection
What is MacConkey?
a selective media used to grow E. coli (showing pink to confirm) and grow Pseudomonas aeruginosa (showing green to confirm)
Differential Media
encourages growth of more than 1 species of bacteria while displaying physical properties or identification (shows pink or green)
Enriched Media
used to grow fastidious bacteria using a specific growth factor that the bacteria desires
Fastidious Bacteria (examples)
bacteria that is difficult to grow, isolate, and stain identify; use Ziehl Neelson stain (acid fast differential stain); outer membrane made of mycolic acid - makes it impossible for dye to permeate
Ex: Mycobacteria (causes tuberculosis (TB) and leprosy)
Ex: Nocardia (causes nocardiosis(respiratory illness)
What is an example of an Enriched Media?
Blood Agar
Reducing Media
AKA Thioglycolate Media; reducing oxygen concentration in media to grow strict obligate anaerobes; add thioglycolic acid to reduce the concentration of oxygen in that media
Oxygen Requirement
the specific oxygen requirements of different microorganisms
List the 3 groupings of microbes according to oxygen requirements
Strict obligate anaerobes; facultative anaerobes; strict obligate aerobes
Strict Obligate Aerobes. Provide an example
organisms that must have oxygen for them to be alive
ex: Microaerophile - only want minute amount of oxygen
Facultative anaerobes
organisms that can survive with or without oxygen
Strict obligate anaerobes. What do they lack?
lack enzymes to break down oxygen (catalase, peroxidase, superoxide dismutase (SOD); leads to oxygen toxicity
Eukaryote Appendages
flagella; cilia; glycocalyx; cell membrane
Eukaryotic Ribosomal Subunits
Small unit: 40s
Large unit: 60s
Together: 80s
What does the “S” stand for in the ribosomal subunits?
Svedberg (centrifugal unit)
Eukaryotic Golgi Apparatus (details)
contain hydrolytic enzymes; 2 faces: cis-pole & trans-pole; release chemical vesicles to encase food and break it down (phagocytize)
What are the 2 faces of the Golgi Apparatus?
cis-pole: closest to ER
trans-pole: furthest from ER
What happens to Golgi Apparatus while phagocytizing it’s food?
becomes phagosome; will break down food and cell will absorb the nutrients
Lysosomes
membrane-close organelles that contain enzymes capable of breaking down various macromolecules; Vesicles can develop into lysosomes
Which 4 macromolecules do Lysosomes breakdown? (Include the enzymes utilized)
Carbohydrates(Carbohydrase); Proteins(Protease); Lipids(Lipase); Nucleic Acid(Nuclease)
Pompe disease
inability to produce carbohydrase; cannot eat food that has sugar in it; will cause liver cirrhosis(cancer)
Tay Sach’s disease
inability to secrete lipase; cannot eat food with oil in it; implicated with mental retardation
Mitochondria (structure details)
is a double-membrane organelle; contains outer and inner membrane and intermembrane space (between the membranes); has cristae; mitochondrial matrix (inner space)
What the function of mitochondria in plants?
Mitochondria is chloroplast in plants (product energy through photosynthesis)
Chloroplast
double-membrane (AKA mitochondria); site for photosynthesis
Diagnosis for Bacterial Cell
test for the bacteria
3 Forms of Bacteria
Coccus; Bacillus; Sprillum
Characteristics of Gram Positive Bacteria
thick cell membrane
peptidoglycan
no outer membrane
no periplasmic space
no lipopolysaccharide (LPS)
no Lipid A(toxic)
no lipoprotein(toxic)
teichoic acid
lipoteichoic acid
Characteristics of Gram Negative Bacteria
thin cell membrane
outer membrane
periplasmic space
lipopolysaccharide (LPS)
Lipid A (toxic)
lipoprotein (toxic)
no teichoic acid
no lipoteichoic acid
Gram Stain
developed by Hans Gram; used to tell differences of chemical composition of cell wall (gram positive vs gram negative)
Narrow Spectrum Drugs
designed to inhibit or destroy only the Gram+ or Gram- bacteria
Broad Spectrum Drugs
designed to inhibit and destroy both Gram+ and Gram- bacteria
Shotgun approach (example)
don’t send sample to lab, just provide broad spectrum drugs for infection
ex: ear infection
3 Types of Genome Transfer between Bacteria
conjugation; transduction; transformation
Conjugation
transfer of genetic material through sex pili; direct contact between donor and recipient
Transduction
transfer of genetic material through bacteriophage (virus that infects bacteria); no direct contact
Transformation
assimilation of degenerated genome from habitat/environment; no direct contact
Sarcinae
morphology of bacteria when they are in multiples of 8 (no more than 64)
R-plasmid
Resistant-plasmid; when patient only takes portion of antibiotics, high mutation of plasma allows bacteria to learn antibiotics and transform to become resistant