Bacterial Genetics/Protein Synthesis Flashcards
Central Dogma of molecular biology
DNA->RNA-> Proteins
Genetics is
Study of gene structure, behavior, inheritance, distribution, variation
who first isolated DNA
Miescher
Nucleic acid structure
Reverse and complementary Strands in a double helix
Why is DNA replication “semi conservative”
Each parent strand acts as a template for a new strand
Prokaryotic DNA structure
Circular chromosomes and plasmids
DNA polymerase III direction
5’-> 3’
precursors used by DNA polymerase III
nucleic acid Triphosphates
DNA Polymerase I activity
DNA repair, lagging strand synthesis
DNA Polymerase II activity
DNA repair
DNA Polymerase III activity
major replication enzyme
Where dos the energy for DNA synthesis come from
Hydrolysis of nucleic acid triphosphates
Processivity
Ability of an enzyme to catalyze many reactions without dissociating from substrate
Helicase activity
Break H-Bonds and unwind DNA
topoisomerase activity
break single strand to prevent supercoiling
DNA gyrase activity
packs and unpacks chromosomes through supercoiling
Primase activity
Starts replication with RNA primers
DNA ligase activity
joins final phosphodiester bond of okazaki fragments
What enzyme lays nucleotides between okazaki fragments
DNA Polymerase I
XerCd recombinase activity
catalyzes crossover to separate dimerized chromosomes
Template strand sense or antisense
Antisense
-35 Box is for…
RNA polymerase recognition site
-10 box function
RNA polymerase binding site
leader sequence
gets transcribed but not translated, contains shine delgarno sequence
mRNA start codon
AUG, generally
First amino acid in most bacterial proteins
formyl-methionine
Polycistronic mRNA
many genes in one mRNA, cleaved later
Subunit of RNA polymerase that regulates transcription initiation
Sigma factor, dissociates after initiation
core promoter
-35 box to +1
Ribosome read direction
5’ -> 3’
Enzyme that catalyzes tRNA attachment to amino acid
aminoacyl-tRNA synthase
Binding site for 16S subunit of Ribosome
Shine delgarno sequence
Which initiation factor prevents premature association of large and small subunits
IF-3
Initiation factor that selects initiator tRNA and palces it at the p site
IF-2, complexed with GTP
Enzyme that catalyzes bind of aminoacyl-tRNA to A site
EF-tu (elongation factor), complexed with GTP
Enzyme that catalyzes peptide translocation
EF-G
Part removed from polypeptide in post-translational protien splicing
inteins
Primary chaperon complex for folding proteins
DNAJ and DNAK
Final chaperon complex for folding proteins
GroEL and GroES
Protein translocation
movement form the cytoplasm to the membrane or periplasmic space
Main translocation pathway for proteins
Sec pathway
Which protein of the Sec pathway keeps the preprotein unfolded
SecB
Type I secretion system
used for adhesion proteins, Sec independant
Type II secretion system
Sec and tat dependent, mostly for hydrolytic enzymes
TAT system
twin arginine secretion, secretes folded proteins with twin arginine in their signal sequence
Type III secretion system
Sec and Tat independent, involved in pathogenicity, forms injectosomes
Type IV secretion system
Can be Sec dependent, used for pathogenicity and conjugation
Type V secretion system
Sec and Tat dependent, used for autotransporting virulence factors and biofilm components
Type VI secretion system
similar to bacteriophage injection system, role in pathogenicity (virulence factors)
