Zamora Test 4/Final Powerpoints

Spring 25 semster

Nucleotide analogs

Inhibits nucleic acid aynthesis

Synthetic amines (amantadine)

Blocks virus uncoating

Pyrophosphate analog (phosphonoformic acid)

A Polymerase inhibitor

Rifamycin

Also a Polymerase inhibitor

Protease inhibitor

Inhibits processing of viral proteins

Interferons

Alter host cells

Drug Resistance

An adaptove response in which microorganisms begin to tolerate an amount of drugs that would normally be inhibitory

genetic versatility and adaptability of microbial population

Drugs resistance is due to __.

Intrinsic as well as acquired

Drug resistance can be __.

Biota

A normal microbial colonist of healthy body surface

Harmless or beneficcal bacrteri

Biota normally consist of __.

“good” biota

Broad spectrum antimicrobials destroys __.

Superinfection

Microbes that were once small in number can begin to overgrown and cause disease

Probiotics

Preparations of live microorganisms fed to animals and humans to improve intestinal biota

replace

Probiotics can __ microbes lost during antimicrobial therapy

Prebiotics

Nutrients that encourage the growth of beneficial microbes in intestine

Bifidobacterium

Fructans encourage the growth of __ in large intestine and discourage the growth of potential pathogens.

Clostridium difficile

Fecal transplants are Used to treat recurrent infection and ulcerative colitis

Fecal transplants

Transfer of feces from a healthy patient via colonoscopy

Recolonize the colon

Fecal transplant work is under way to develop a pill containing the species to __.

The effect of the drug on the host must be considered

If a drug is administered to the host even though its target is a microbe.

Gene

The functional unit of genetic information is a __.

DNA

Genes in cells are composed of __.

DNA> RNA> Protein

Three informational macromolecules in cell

DNA

Information stored in __

RNA

Switches information from DNA to Protein

Replication, Transcription, and Translation

Genetic information flow can be divided into three stagesRepl

Replication

DNA is duplicated

Transcription

Information from DNA is transffered to RNA

Translation

Information in RNA is used to build polypeptides

mRNA (messenger RNA)

Encodes polypeptides

tRNA (transfer RNA) & rRNA (ribosomal RNA)

Plays a role in protein synthesis

Nucleotide

A __ contains a phosphate group, a sugar molecule, and a nitrogen containing base

Chargaff’s rule

number of A=T, number of C=G

Double helix

DNA is a __ of two nucleotide strands

Base pairs

Complementary __ hold two DNA strands together

Hydrogen bonds

__ form between complementary bases.

Circular

Prokaryotes have __ DNA helix

Linear chromosomes

Eukaryotes have __.

DNA replication

__ is necessary for cell division.

DNA ligase

Connects short pieces of DNA together to make long pieces of DNA.

DNA primase

“gets everything going?”

DNA gyrase

Which enzmye is required for bacteria

DNA polymearse

__ catalyze the addition of dNTPs.

Five

__ different DNA polymerase in E. coli

DNA polymerase III

__ is the primary enzyme replicating chromosomal DNA

RNA

DNA polymerase require a primer made from __

semi-conservative and bidirectional

DNA replication is __

700 nucleotides per second

DNA replicate rate: up to __

one parental and one new strand

DNA replication is semiconservative because each of the two progeny double helices have __

Deoxynucleoside 5’ triphosphate (dNTP)

Precursor of each nucleotide is a __.

the 5’ end to the 3’ end

DNA replication ALWAYS proceeds from __.

Replication origin

DNA synthesis begins at the __ in prokaryotes.

Replication fork

Unwound DNA where replication occurs

DNA helicase

__ unwinds the DNA

Continuosly

Extension of DNA occurs __ on the leading strand.

Discontinuously

Extension of DNA occurs __ on the lagging strand. (Okazaki fragments)

1 mistake per billion base

1 mistake per 10,000 base pairs reduced to __ (DNA replication errors)

Complementary DNA strands

Several repair enzymes use __ to repair damage.

RNA polymerase

Transcription (DNA to RNA) is carried out by

DNA

RNA polymerase uses __ as template

ATP, GTP, CTP, and UTP

RNA precursors are

5’ to 3’

Transcription chain growth is __ just like DNA replication

Adenine, guanin, cytosine, uracil

Four bases in RNA structure

the 4 bases, ribose sugar, phosphate

RNA uses __, __, and __ to form a Sugar-phosphate backbone

mRNA (messenger RNA), tRNA (transfer RNA), rRNA (ribosomal RNA)

Three type of RNA

mRNA

Translation produces a protein molecule with an amino acid sequence determined by the nucleotide sequence in the __ (Eukaryotic Transcription)

rules

RNA synthesis relies on complementary base pairing__

Chromsome to ribosome

Transcription - Nucleotide message sent from __

• (DNA nucleotide sequence "copied" (using
  complementary base pairing) as a
  "messenger" nucleotide sequence of RNA
  (mRNA))

DNA replication and DNA polymerase

RNA polymerase catalyzes synthesis of mRNA; similar to _

RNA polymerase

Promoter sequence binds __

Termination signal

__ ia a sequence of nucleotides at end of genes that tell RNA polymerase to stop transcription

NOT transcribed

The entire DNA molecule in a chromosome is __, only a specific gene or family of genes is transcribed

Unit of transcription

Unit of chromosome bounded by sites where transcription of DNA to RNA is initiated and terminated

RNAs

Most genes encode proteins, but some __ are not translated (i.e., rRNA, tRNA)

16s, 23s,and 5s

Three types of rRNA.

Very stable

rRNA and tRNA are __

cotranscribed

tRNA __ with rRNA or other tRNA

short half-lives

mRNA have __ (a few minutes)

single mRNA

Bacteria often have genes clustered together. These genes are transcribed as a __

Polycistronic mRNA

An mRNA encoding a group of cotranscribed genes is called a __

Operon

A group of related genes transcribed on a polycistronic mRNA. This allows for expression of multiple genes to be coordinated

RNA polymerase

Eukaryotes have multiple __

RNA polymerase I

Transcribes genes for two large rRNA

RNA polymerase II

Transcribes protein-encoding genes

RNA polymerase III

Transcribes genes for tRNA, 5s RNA and other small RNA molecules

Distinct promoter

Each class of RNA polymerase recognizes a __

COding and noncoding regions

Eukaryotic genes have __

Exons

Coding sequences

Introns

Intervening sequences

Primary transcript

Both introns and exons are transcribed into the __

Excision, Splicing

Functional mRNA is formed by __ of introns and __ of exons (preformed by the spliceosome)

RNA capping

Addition of methylated guanine to 5’ end of mRNA

Poly (A) tail

Addition of 100-200 adenylate residues; Stabilizes mRNA and is required for translation

Translation of protein synthesis

Nucleotide sequence of mRNA used to synthesize a sequence of amino acids (polypeptide or protein)

ribosomes

Protein synthesis translation occurs using __

mRNA codons

__ are used to specify amino acids

read

Ribosomes “__” mRNA codons to synthesize a specific amino acid sequence

“carrier” transfer RNA (tRNA)

Each of the 20 amino acids has a specific __ that brings the amino acid to the ribosome

Amino acid sequence

Complementary base pairing between the maRNA and TRNAs determine the __