Thursday, March 28, 2013

BLOG 9 - Reflection

REFLECTIONS OF ANTIMICROBIAL DRUGS FROM CHAPTER 10

Penicillin

Penicillin
·          Bind to and deactivate the enzyme that cross links the NAM subunits of peptidoglycan
·          Natural drugs have limited action against most Gram – (G-) bacteria because they do not readily cross the outer membrane
·          Synthetic drugs have broader spectra of action
·          Allergic reactions against beta-lactams in some adults; monobactams are least allergenic


 

Vancomycin

Vancomycin
·          Directly interferes with the formation of alanine-alanine bridges between NAM subunits
·          Affective against most G+ bacteria but generally reserved for use against strains resistant to other drugs such as; Methicillin-resistant staphylococci aureus (MRSA)
·          Damage to ears and kidneys, allergic reactions

 



Streptomycin

 
Streptomycin
 
 
 
 
 
 
·          Inhibit protein synthesis by irreversibly binding to the 30S subunit of prokaryotic ribosomes
·          bactericidal by destroying outer membrane of G-bacteria
·          Broad (effective against G+ and G- bacteria
·          Damage to ears and kidneys, allergic reactions

 
 


Erythromycin

Erythromycin
·           Act by binding to the 50S subunit of prokaryotic ribosomes and preventing the elongation of the nascent protein
·          Effective against G+ and a few G- bacteria
·          Nausea, mild gastrointestinal pain, vomiting; erythromycin increases risk of cardiac arrest






Tetracycline

Tetracycline
·          Prevents tRNA molecules, which carry amino acids, from binding to ribosomes at the 30S subunit’s docking site
·          Most are broad (effective against many G+ and G- bacteria as well as against bacteria that lack cell walls, such as Mycoplasma
·          Nausea, diarrhea, sensitivity to light, forms complexes with calcium, which stains developing teeth and adversely affects the strength and shape of bones

































Thursday, March 21, 2013

BLOG 8 - ENCOUNTER


BLOG 8: ENCOUTER WITH MOLDED STRAWBERRIES


I was never really was a big fan of eating strawberries, I always stayed far away from them. I never tasted strawberries to even dislike them but it was something about them that made me not want even give it a taste trial. I fell in love with them one day when I was hungry and I ate without one ounce of hesitation and history took its place from there. But, the most stomach gnawing feeling came upon me when i went into the fridge and saw that the strawberries grew mold! Ewwwwwwww! I was so disgusted I didn't even bothered to eat the others that had no mold. I took it out of the fridge and analyzed it more carefully as i expressed a very disgusted look on my face. It had white or grayish projections pointing out and it made my skin crawl. I then threw it away and retrieve to do research as to why strawberries get mold and what exactly is it that causes the mold.


Why do strawberries get mold?

- moisture is the main cause of mold on strawberries


How do strawberries get mold?

- An excess of moisture causes botrytis fruit rot, also known as gray mold

- The gray mold affects the petals, flower stems, fruit caps and fruit of strawberry plants

- Gray mold is a result of the botrytis cinerea fungus

Tuesday, March 5, 2013

BLOG 7- DEFINITIONS

BLOG 7:
"MICROBIAL GENETICS DEFINITIONS"

Definitions for the structure and replication of genomes

Genetics
- is the study of inheritance and inherited traits


 

Genes
- are composed of specific sequences of nucleotides that code for polypeptides that code for polypeptides or RNA molecules


 
Genome
- is the sum of all the gentic material in a cell or virus

efinitions for the structure of Nucleic Acid

Base Pairs (BP)
- describes the two strands of DNA that are held together by hydrogen bonds between complementary bases of nucleic acids

Definitions for the structure of prokaryotic genomes

Chromosomes
- typically circular molecules of DNA associated with protein and RNA molecules in nucleotide  


 

Nucleotides
- localized area of the cytoplasm


 
Plasmids
- extrachromosomal DNA molecules found in prokaryotic cells


Histones
- proteins found in eukaryotic cell chromosomes


Nucleosomes
- beads of DNA; that clump with other proteins to form chromatin fibers

Definitions for DNA replication

Leading strand
- is synthesized toward the replication fork


 
Lagging strand
- is synthesized in a direction away from the replication replication fork, and discontinually in Okazaki fragments


 

Methylation
- a cell addds a methyl group to one or two bases that are part of specific nucleotide sequences