BACTERIAL MORPHOLOGY Flashcards
memorization
The shape of the bacteria is determined by the mechanism of _____ assembly:
Cell wall
Mention 3 organisms with a shape described as “spirochete”:
Remember “BLT” or ‘BoLeT”
- Borrelia
- Leptospira
- Treponema
Lancet-shaped diplococci:
Streptococcus pneumoniae
Coffee bean-shaped diplococci:
Neisseria gonorrhoeae
With tapered/tapering ends bacteria:
Fusobacterium
example of palisade arrangement bacteria:
Corynebacterium
“picket fence”. “Chinese letter arrangement”
Corynebacterium diphtheriae
Unit of measurement of bacteria:
Micrometer
Smallest pathogenic bacillus
Haemophilus
Largest pathogenic bacillus
Bacillus anthracis
Mucilaginous envelope that surrounds some bacteria
Capsule
The capsule of Bacillus anthracis is made of:
Poly-D-glutamic acid
A test that detects capsules in bacteria:
Quellung reaction
Enumerate encapsulated microorganisms:
- Streptococcus pneumoniae
- Neisseria meningitidis
- Klebsiella pneumoniae
- Haemophilus influenza
- Salmonella typhi
- Cryptococcus neoformans
- Pseudomonas aeruginosa
Mnemonic: “Some Nasty Killers Have Some Capsule Protection”
Special staining methods for capsules:
- Hiss stain
- India Ink stain (negative stain) (stains the background)
Loosely arranged extracellular material that surrounds bacterial cells; found in biofilm
Slime layer
Known bacteria that use biofilm to adhere to surfaces, like catheters/artificial implants
Staphylococcus epidermidis
Also known as the peptidoglycan layer or murein layer; protects bacteria against osmotic pressure; gives shape to bacteria; confer the gram’s reaction of the bacteria
Cell wall
It is composed of a very thick protective peptidoglycan (murein layer);
Gram-positive cell wall
Gram (+) cell wall consists of glycan chain of alternating _________ (NAG) and ___________ (NAM)
N-acetyl-D-glucosamine (NAG)
N-acetyl-D-muramic acid (NAM)
Negatively charged and contributes to the negativity of the cell wall; it may also bind and regulate the movement of cations into and out of the cell:
Teichoic acid
Composed of a thin layer of peptidoglycan. No teichoic acid:
Gram-negative cell wall
Between outer membrane and gram-negative cell wall:
Periplasmic space
Concurs resistance to drying and chemicals; contains a waxy layer of glycolipids and fatty acids (hydroxymethoxy acid or mycolic acid) bound to the exterior of the cell wall)
Acid-fast cell wall
The acid-fast cell wall has a gram-_____ reaction.
gram-positive
enumerate Acid-Fast organisms:
Mnemonic: “No MILCC”
Nocardia
Mycobacterium
Isospora
Legionella micdadei
Cryptosporidum
Cyclospora
Additional information: Acid-Fast protozoans (ICC)
- Isospora
- Cryptosporidium
- Cyclospora
Bacteria without cell wall but contain sterol in their cell membrane:
Mnemonic: MU/ “MU palang, hubad na”
- Mycoplasma
- Ureaplasma
The outer membrane is present only in gram-______ bacteria:
gram-negative bacteria
The lipopolysaccharide in the outer membrane is composed of:
- Lipid A - major constituent; toxic
- Core polysaccharide
- O polysaccharide
Endotoxin is ONLY found in gram-_____ bacteria:
Endotoxin is only found in gram-negative bacteria
All gram-positive organisms DO NOT HAVE ENDOTOXIN except:
Listeria monocytogenes
Site of bacterial energy metabolism; ATP production:
Cell membrane
From what bacteria are Babes-Ernst granules recognized?
Corynebacterium diphtheriae
Remember: “CORNY (Coryne) mo BABE (Babes-Ernst)”
From what bacteria are Much granules recognized?
Mycobacterium tuberculosis
From what bacteria are Bipolar bodies recognized?
Yersinia pestis
Bacteria that resembles a “safety pin”
Yersinia pestis
Survival response to certain adverse nutritional conditions, such as depletion of certain resources; highly resistant to desiccation, heat, and various chemicals:
Endospores
Endospores help identify some species of bacteria like:
Bacillus and
Clostridium
What microorganism has a terminal spore described as having a “tennis racket” appearance?
Clostridium tetani
What microorganism has a subterminal spore?
Clostridium botulinum
What microorganism has a central spore described as having a “Boxcar” appearance?
Bacillus anthracis
The structure of endospores possesses a core that contains many cell components, a spore wall, a cortex, a coat, and an exosporium. the core contains ___________, which aids in heat resistance within the core.
Calcium dipicolinate
Endospore stains:
- Schaeffer-Fulton stain
- Doemer’s stain
- Wirtz-Conkin
Endospore stain that stains any present endospores green:
Schaeffer-Fulton stain
What does bacteria use for locomotion:
Flagella
No flagella:
Atrichous
Single flagellum at one pole:
Monotrichous
Single flagellum at each pole:
Amphitrichous
Tuft of flagella at one or both poles:
Lophotrichous
Flagella all over organism:
Peritrichous
Pathogens that possess monotrichous flagella:
- P. aeruginosa
- Campylobacter
- Helicobacter
- Vibrio
Pathogens that possess peritrichous flagella:
Most members of the Enterobacteriaceae except “SKY” @ 55C)
To differentiate bacteria through motility:
- Shigella (?) from Salmonella (?)
- Klebsiella (?) from Enterobacter (?)
- Shigella (-) from Salmonella (+)
- Klebsiella (-) from Enterobacter (+)
Often motility can be seen best at ___C (35-37C may be inhibitory)
25C
Flagella stains contains ______ that precipitates and coats flagaella
contains tannic acid
aka axial filament, found in spirochetes:
Endoflagella
Characteristic motility:
Tumbling motility:
Listeria
Characteristic motility:
Darting motility:
Campylobacter
Characteristic motility:
Gliding motility:
Capnocytophaga
Remember: “CAP-tain America hindi lumilipad, pero nagga-GLIDING” - Doc Gab Pascual XD
Characteristic motility:
Swarming motility:
Proteus, some Bacillus species
Hair-like extensions that extend into the environment; has 2 types used for attachment and for conjugation:
Pili/Fimbriae
