Ch. 6 - Biochemical Basis of Life: chemical and genetic aspects of microorganisms) Flashcards
DF Biochem
The chemistry of living cells
DF: hydrocarbon
Organic molecule that contains only carbons and hydrogen atoms
DF cyclic compounds
Carbon atoms linked to other carbon atoms to close a chain
Carbohydrate formula
1C : 2H : 1O
Dehydration synthesis
Combination of 2 monosaccharides following the removal of water
Hydrolysis reaction
disaccharides react with water to break into individual monosaccharides
What is the biochem of peptidoglycan?
A repeating disaccharide attached to proteins to forma lattice that surrounds the bacterial cell.
2 Main functions of polysaccharides
1) Stores energy as glycogen/starch
2) Provides a tough molecule for structural support/protection
Saturdated fatty acids
Monounsaturated fatty acids
Ployunsaturated fatty acids
sat. - single bonds, solid at room temp
monounsat- one double bond, butter, olives, peanuts
polyunsat- 2+ double bonds, soybeans,corn
What are waxes
saturated fatty acid + long chain alcohol
Glycerophospholipids & sphingolipids
Glycerophospholipids: glycerol backdone, 2 fatty acids,, PO4-alcohol
sphingolipids: sphingosin, fatty acid, PO4-choline
The outter membrane of gram (-) bacteria contain ___, but gram (+) dont
LPS: lipopolysaccharaide (lipid+polysaccharide)
Lecithins and cephalins
glycophospholipids in brain/nerve tissue, and egg yolk
Sphingolipids
found in brain/nerve tissues and makes up the myelin sheath
Glycolipids
brain and myeline sheath
Prostaglandins and leukotrienes
wide effects on body chemistry and blood pressure.
Leukotrienes can produce long lasting muscle contractions
___ are the most essential chemical in all living cells
Protein
What type of bond connects individual amino acids?
peptide bond (covalent)
Protein structure
1’ - linear sequence of amino acids
2’ - twisting/coiling of the amino acid chain (a-helix/B-sheath)
3’ - folding or entwining of the chain (3D structure)
4’ - Bonding of 2+ polypeptide chains to make complex protein molecules
DF enzyme
Specialized protein molecules produced by living cells
Apoenzymes
Only function when linked with a nonprotein cofactor or coenzyme
cofactors
calcium, iron, magnesium…
coenzymes
vitamin type compound
Holoenzyme
the unit of enzyme + cofactor
Central Dogma of DNA Replication
DNA —transcription—> RNA —translation—> Protein
RNA vs DNA (3)
- DNA contains deoxyribose as its pentose ; RNA contains ribose as its pentose
- DNA contains thymine ; RNA contains uracil
- RNA can leave the nucleus and DNA cannot
Pyramidines
C U T
Purines
A, G
What type of bond holds together the double helix/base pairs of DNA?
Hydrogen bond
Which enzyme is most important for DNA replication?
DNA polymerase
Inducible genes
Genes that are only expressed when the gene products are needed
Constitutive genes
Genes that are expressed at all times
What is the primary enzyme involved in transcription?
RNA polymerase
Why can both transcription and translation occur at the same time in prokaryotes only?
Transcription and translation both occur in the cytoplasm so ribosomes can attache to the mRNA molecules as they are being transcribed. Whereas, in eukaryotes, transcription occurs int he nucleus
Ribosome protein formation
A site - tRNA with anticodon enters the ribosome
P site - amino acid binds to polypeptide chain
E-site - tRNA exits alone from here
