Nucleic Acids And Proteins Flashcards
Nucleotides
A unit of nucleic acid comprising a phosphorylated ribose sugar and a nitrogen base.
Purines
Nitrogen bases with a double-ring structure.
Adenine and Guanine.
Hybridization
In nucleic acids, the formation of hydrogen bonds between complementary strands of DNA or RNA.
Okazaki Fragments
Intermediate products of DNA synthesis on the lagging strand.
Nick Translation
Addition of labeled nucleotides at nicks (single-strand breaks) in DNA.
Restriction Enzyme
An endonuclease isolated from bacteria that will break single- or double-stranded nucleic acids at specific sequences.
Ribosome
Complex of RNA and proteins that catalyze formation of peptide bonds.
Adenine
One of the common nitrogen bases in DNA and RNA.
Pyrimidines
Nitrogen bases with a single-ring structure. Cytosine, Thymine, and Uracil.
Template
A region of single-stranded nucleic acid used as a guide for replication or synthesis of a complementary strand.
Primer
A short, single-stranded DNA fragment designed to primer synthesis of a specific DNA region.
Ligase
An enzyme that forms one phosphodiester bond connecting two preexisting fragments of DNA.
Overhangs
Stretch of unpaired nucleotides in the end of a DNA molecule.
Deoxyribose
Ribose without a hydroxyl group (OH) on the carbon in the 2 position on the sugar ring.
Cytosine
One of the common nitrogen bases in DNA and RNA.
Complementary
The order of two anti parallel single-stranded nucleic acids such that A on one strand is always across from T on the other strand, and C is always across from G.
Semi-conservative
A term used to describe DNA replication where one strand is conserved and serves as a template for a new strand, resulting in a new double helix comprising one parent and one daughter strand.
Holoenzyme
A multisubunit protein with enzymatic function.
Enzyme
A protein that acts as a biological catalyst.
Endonuclease
An enzyme that separates DNA or RNA by cutting within the linear molecule.
Sticky ends
An end of DNA double helix at which a few unpaired nucleotides of one strand extend beyond the other, can hybridize with a complementary strand.
Oligonucleotide
Short fragments of DNA or RNA.
Guanine
One of the common nitrogen bases in DNA and RNA.
Mismatches
When an incorrect base was added.
Replication fork
DNA undergoing replication can be observed as a forked structure.
Exonuclease
An enzyme that removes nucleotides from DNA or RNA from either end of the linear molecule.
Helicase
An enzyme that untangles DNA by cutting and ligating one of both strands of the double helix for DNA replication.
Promoter
DNA sequences that bind RNA polymerase and associated factors.
rRNA
Ribosomal RNA. Ribonucleic acid that serves as a structural and functional component of ribosomes.
Thymine
One of the common nitrogen bases in DNA and RNA.
Antiparallel
Two complementary single-stranded nucleic acids oriented so that when hydrogen-bonded together through complementary bases, the 5’ end of one molecule is next to the 3’ end of the other.
Proofread
A correction function of the DNA polymerase complex that repairs errors committed during DNA replication.
Hairpin
A fold in DNA or RNA that forms a short double strand along the single strand.
Transcription
Template-guided synthesis of RNA by RNA polymerase.
MRNA
Messenger RNA. Ribonucleic acid that carries information from DNA in the cell nucleus to ribosomes in the cytoplasm.
Cytoplasm
Material in cell excluding the cell nucleus.
Ribose
A 5 carbon sugar
Poly A
RNA polymerase that adds adenine nucleotides to the 3’ end of mRNA. The resulting polyA tail is important for mRNA stability and translation into protein.
Open Reading Frame
DNA section marked with start and end codons.
Peptide Bond
Covalent carbon-nitrogen bonds that connect amino acids in proteins.
Beta Pleated Sheets
Part of the common motif of the regular protein secondary structure. Beta sheets consist of beta strands (β-strands) connected laterally by at least two or three backbone hydrogen bonds, forming a generally twisted, pleated sheet. A β-strand is a stretch of polypeptide chain typically 3 to 10 amino acids long with backbone in an extended conformation.
Cis Factors
Binding sites for one or more trans-acting factors on RNA involved in the initiation and control of RNA synthesis.
Trans Factors
Proteins that bind to cis factors and direct the assembly of transcription.
RNA Dependent RNA Polymerases
Enzymes that synthesizes RNA using RNA as a template.
Cap
7-methyl G 5’ppp 5’ G/A covalently attached to the 5’ end of messenger RNA
Polypeptide
Protein
Codon
A three nucleotide sequence that will guide the insertion of a specific amino acid into protein.
DNA Polymerase
Enzyme to catalyze DNA replication.
Introns
Sequences in DNA that interrupt coding sequences.
miRNA
MicroRNA. Regulatory RNAs, 17-27 nucleotides in length, derived from RNA hairpin structures, control gene expression by pairing with imperfectly complementary sequences in mRNAs to inhibit translation.
Proteome
All of the proteins that make up a cell.
RNA Polymerase
An enzyme that catalyzes the template-dependent formation of phosphodiester bonds between ribonucleotides forming ribonucleic acid.
Mutation
A change in the order or sequence of nucleotides in DNA found in less than 1% to 2% of a given population.
Exons
Sequences of DNA that code for protein.
Gene
An order or sequence of nucleotides on a chromosome that contain all of the genetic information to make a functional protein or RNA product.
Alpha Helices
Secondary structure of proteins. Ribbon like structure composed of chains of amino acids hydrogen bonded through their side chains.
P Site
Peptidyl site, location of charged tRNA binding in the ribosome complex. Second binding step for tRNA. Holds a tRNA carries the growing polypeptide chain. Moves to E site next.
tRNA
Transfer RNA. Adaptors that link codons in messenger RNA with amino acids.
Peptidyl Transferase
Ribosome that catalyzes the formation of a peptide bond.
Splicing
Removal of intron sequences from mRNA.
Domains
A functional part of the protein.
Oligomers
A short sequence of amino acids.
A Site
Location of incoming charged tRNA binding in the ribosome complex for acceptance of the growing peptide. First step.
Peptide
Polymer of a few amino acids.
Phosphodiester Bonds
Covalent attachment of the hydroxyl oxygen of one phosphorylated ribose sugar to the phospate phosphorous of the next.
Hydroxyl Group
OH
Nucleoside
A nitrogen base bound to an unphosphorated sugar. Adenosine, Guanosine, Cytidine, and Thymidine.
Denaturing Agents
Formamide or Urea. Displace hydrogen bonds and seperate the two strands of the helix.
Sugar-phosphate Backbone
5 carbon sugar and phosphate chain that connects to the nucleic acids.
Terminal Tranferase
A type of DNA polymerase that can synthesize polynucleotide chains without a template.
Methyltransferases
Catalyze the addition of methyl groups to nitrogen bases, usually adenines and cytosines.
Recombination
The mixture and assembly of new genetic combinations.
Recombinant Molecule
One that holds a new combination of DNA sequences
Transduction
Transfer of genetic information from one cell to another through a viral intermediate.
Bacteriophage
Virus that infects bacteria.
Transformation
Transfer of genetic information among cells without physical association, such that a new phenotype is produced in the recipient cells.
Protease
An enzyme that degrades protein.
Ribonuclease
An enzyme that degrades RNA.
Gene Expression
Production of RNA and protein using a DNA template.
Ribosomal RNA
rRNA.
