Tick Vectors

Antimicrobial Agents - Inhibition of DNA and Protein Synthesis

Bacterial chromosome replication

DNA replication

Bacterial Topoisomerases 

maintain DNA in appropriate state of supercoiling 

cut and reseal DNA

DNA gyrase (topoisomerase II) introduces negative supercoils 

Topoisomerase IV decatenates circular chromosomes 

these are the targets of the quinolone antibacterial agents 

Quinolones

bind to bacterial DNA gyrase and topoisomerase IV after DNA strand breakage 

prevent resealing of DNA 

disrupt DNA replication and repair 

bactericidal (kill bacteria)

Fluoroquinolone is particularly useful against

Gram +ves: Staphylococcus aureus, streptococci 

Gram -ves: Enterobacteriacea; Pseudomonas aeruginosa 

Anaerobes: e.g. Bacteroides fragilis 

many applications e.g. UTIs, prostatitis, gastroenteritis, STIs 

Adverse effects

Relatively well tolerated

GI upset in ~ 5% of patients 

allergic reactions (rash, photosensitivity) in 1 - 2% of patients 

Inhibition of Bacterial Protein Synthesis 

Macrolides 

in 1952: Erythromycin was isolated as the first macrolide (Streptomyces erythreus) 

Newer macrolides: clarithromycin, azithromycin 

Structurally they consist of a lactone ring (14- to 16-membered) + two attached deoxy sugars 

Mode of action 

bind reversibly to bacterial 50S ribosomal subunit 

causes growing peptide chain to dissociate from ribosome → inhibiting protein synthesis 

bacteriostatic (stops reproduction)

Macrolides’ spectrum of activity

good antistaphylococcal and antistreptococcal activity 

treatment of respiratory & soft tissue infections and sensitive intracellular pathogens • e.g. Chlamydia, Legionella 

Adverse effects

Generally well tolerated

nausea 

vomiting 

diarrhoea 

rash 

Aminoglycosides

large family of antibiotics produced by various species of Streptomyces (“mycin”) and Micromonospora (“micin”) 

include: streptomycin, neomycin, kanamycin, gentamicins, tobramycin 

Structure = linked ring system composed of aminosugars and an aminosubstituted cyclic polyalcohol 

Mode of action of aminoglycosides

Bind irreversibly to 30S ribosomal subunit 

disrupt elongation of nascent peptide chain 

translational inaccuracy → defective proteins 

bactericidal 

Spectrum of activity 

broad spectrum; mainly aerobic G-ve bacilli (e.g. P. aeruginosa) 

used to treat serious nosocomial infections (hospital acquired infections)

First TB antibiotic

Used for cystic fibrosis 

Adverse effects

all aminoglycosides have low Therapeutic Index (only a small amount needed to become toxic)

renal damage, ototoxicity, loss of balance, nausea 

Microbiology Mnemonics

Hi, everyone!! I’ve had a studyblr for about a week now and have already met so many kind, supportive people. I couldn’t be more thankful. That said, I really wanted to give back to such an amazing community! So here’s my first printable for you! 

It includes:

a 5AM-10PM schedule (for my early hustlers)

‘Top 3 Priorities’ + ‘Can Wait’ categories

a ‘To-Do’ list

Daily Goals, Notes, Doodles

a water tracker (stay hydrated, friends!)

10 Good Things (reflect back on your day and jot down the little things that made you happy even if your day wasn’t the greatest)

They’re available for download in PDF and PNG formats + in pink, blue, yellow, and white! I’ve also made a grid and grid-less version! 

Grid

Blue: pdf / png Pink: pdf / png White: pdf / png Yellow: pdf / png

No Grid

Blue: pdf / png Pink: pdf / png White: pdf / png Yellow: pdf / png

And here’s a link to the entire folder on my DropBox!

Please tag me with #arystudies or mention me if you use these!! I’d love to see them in action. :’) I’m also really curious to see what you all think of them, so please let me know!! 

Be sure to check out my monthly calendars too!

Happy studying!  

Another Harry Potter Mnemonic (yayyy!!!)

So, whenever I read about this fungi Sporothrix schenckii I think about Bellatrix Lestrange… geti it? 

Sporothrix - Bellatrix

That evil deatheater that killed Sirius Black. But they actually got it wrong in the movie, she doesn’t “Avada Kedavra” him, she just knocked him through that veil where you could hear death people….

Ok, enough with the Harry Potter fact.

To diagnose an infection from Sporothrix schenckii, you have to see this cigar shaped yeasts (from the pus of the lesions), which are the tissue form of the fungi. 

So to remember this, just picture:

“Bellatrix Lestrange smoking a cigar”

(Sporothrix: cigar shaped yeast in pus)

Hey guys, since my previous post on Morning Routines was very well received,  I decided to make a night version. This small infographic thingy outlines the things I do at night to prep myself for rest, as well as some other things you could try to ensure you get a good night’s sleep. Hope this helps, and don’t hesitate to drop me an ask if you have any questions!

P.S. the typefaces used are Bromello and Montserrat

Antimicrobial Agents - Inhibition of DNA and Protein Synthesis

Bacterial chromosome replication

DNA replication

Bacterial Topoisomerases 

maintain DNA in appropriate state of supercoiling 

cut and reseal DNA

DNA gyrase (topoisomerase II) introduces negative supercoils 

Topoisomerase IV decatenates circular chromosomes 

these are the targets of the quinolone antibacterial agents 

Quinolones

bind to bacterial DNA gyrase and topoisomerase IV after DNA strand breakage 

prevent resealing of DNA 

disrupt DNA replication and repair 

bactericidal (kill bacteria)

Fluoroquinolone is particularly useful against

Gram +ves: Staphylococcus aureus, streptococci 

Gram -ves: Enterobacteriacea; Pseudomonas aeruginosa 

Anaerobes: e.g. Bacteroides fragilis 

many applications e.g. UTIs, prostatitis, gastroenteritis, STIs 

Adverse effects

Relatively well tolerated

GI upset in ~ 5% of patients 

allergic reactions (rash, photosensitivity) in 1 - 2% of patients 

Inhibition of Bacterial Protein Synthesis 

Macrolides 

in 1952: Erythromycin was isolated as the first macrolide (Streptomyces erythreus) 

Newer macrolides: clarithromycin, azithromycin 

Structurally they consist of a lactone ring (14- to 16-membered) + two attached deoxy sugars 

Mode of action 

bind reversibly to bacterial 50S ribosomal subunit 

causes growing peptide chain to dissociate from ribosome → inhibiting protein synthesis 

bacteriostatic (stops reproduction)

Macrolides’ spectrum of activity

good antistaphylococcal and antistreptococcal activity 

treatment of respiratory & soft tissue infections and sensitive intracellular pathogens • e.g. Chlamydia, Legionella 

Adverse effects

Generally well tolerated

nausea 

vomiting 

diarrhoea 

rash 

Aminoglycosides

large family of antibiotics produced by various species of Streptomyces (“mycin”) and Micromonospora (“micin”) 

include: streptomycin, neomycin, kanamycin, gentamicins, tobramycin 

Structure = linked ring system composed of aminosugars and an aminosubstituted cyclic polyalcohol 

Mode of action of aminoglycosides

Bind irreversibly to 30S ribosomal subunit 

disrupt elongation of nascent peptide chain 

translational inaccuracy → defective proteins 

bactericidal 

Spectrum of activity 

broad spectrum; mainly aerobic G-ve bacilli (e.g. P. aeruginosa) 

used to treat serious nosocomial infections (hospital acquired infections)

First TB antibiotic

Used for cystic fibrosis 

Adverse effects

all aminoglycosides have low Therapeutic Index (only a small amount needed to become toxic)

renal damage, ototoxicity, loss of balance, nausea 

Remember to use your sponge to replace any bacteria on your dishes accidentally removed by the act of eating.

Microbiology professor (via scienceprofessorquotes)

nasty moodboard

Microbiology Mnemonic

STD: Chlamydia Trachomatis’ serotypes

“Eye Don't Know why people don’t use condoms”

Most common BACTERIAL STD in the US

Serotypes: D-K : nongonococcal urethritis, cervicitis, PID

Eye: Inclusion conjunctivitis. 

Pneumonia (staccato cough) / Inclussion conjunctivitis in neonates / infants

STD: L imphogranuloma Venereum

L1,2,3

Africa, Asia, South America

Swollen lymph nodes, ulcers, fistulas -> Genital elephantiasis

tr AC homa

A-C serotypes (A,B,Ba,C)

Follicular conjuntivitis -> Conjuntival scarring -> inturned eyelashes -> corneal scarring -> BLINDNESS

Parasitology