Microbial genomics Flashcards
Where does transcription and translation occur in prokrayotes/eukaryotes?
Prokaryotes: both occur in the cytoplasm
Eukaryotes: Transcription occurs in the nucleus, Translation occurs in the cytoplasm
What is a gene?
A gene is a RNA or DNA sequence that encodes the synthesis of the gene product
What is an operon?
a set of structural genes that are regulated together, depending on the cell
metabolic requirements
How is a bacterial promoter structured?
RNA‐polymerase
Sigma‐factor: required for the polymerase to recognize the promotor
Describe Sanger sequencing.
Copies of the original sequence is made in a process similar to PCR
Large amounts of dNTPs and small amounts of ddNTPs are added
ddNTPs are missing 3’‐hydroxyl and incorporation means that synthesis is stopped
The ddNTPs are marked with fluorescence molecules
Fragments are separated and fluorescence are identified
For short sequences (800 bp)
Describe the general procedure of genome assembly
Putting the sequenced fragments together in correct order and removing “overlaps”. The computer searches for overlaps and arrange them to a consensus sequence
Describe the general procedure of genome annotation
Translating the raw‐data into a list of the genes and other important functional sequences in the genome
Finding start and stop codons
Start codon should be near an RBS
It is a higher probability that an ORF is functional if the ORF is similar to ORFs in other organisms
What is a mutation?
a heritable change in the DNA sequence
Describe the Baltimore classification of viruses.
a system used to classify viruses based on their manner of messenger RNA (mRNA) synthesis
What are retroviruses?
viruses that insert a copy of their RNA genome into the host’s DNA in order to replicate.
Describe the replication of HIV in detail.
1) binding, 2) fusion, 3) reverse transcription, 4) integration, 5) replication, 6) assembly, and 7) budding.
What are antigenic drift and antigenic shift among influenza Virus
Antigenic drift creates influenza viruses with slightly modified antigens, while antigenic shift generates viruses with entirely new antigens
