Transcript Chemistry and proteins

Chemistry and proteins
Ms. Kim L. Jensen
LHS Biology
2002-2003
Protein synthesis
• Messenger RNA (mRNA) is the template for protein
synthesis.
• It consists of a series of nucleotides, each containing one of
four nitrogenous bases, Uracil, Cytosine, Adenine, and
Guanine.
• The order of nucleotides in a strand of mRNA specifies the
order in which amino acids are added as a protein is built.
Each series of three nucleotides specifies one amino acid.
• This chart identifies each amino acid by its three-letter
codon(s). For example, G under the "first letter" column, C
under the "second letter" column, and A under the "third
letter" column intersect at alanine, the amino acid specified
by the sequence GCA. Most amino acids are identified by
more than one codon (for instance, GCU, GCC, GCA, and
GCG all encode alanine).
Genetic Code
TRYPTOPHAN (Essential
Amino Acid)
• A natural relaxant, helps
alleviate insomnia by
inducing normal sleep;
• anxiety & depression;
• migraine headaches;
• helps the immune system;
• helps reduce the risk of
artery & heart spasms;
• works with Lysine in
reducing cholesterol levels.
LYSINE (Essential Amino
Acid)
For Cold Sores!!!
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absorption of calcium;
helps form collagen ( which makes up
bone cartilage & connective tissues);
aids in the production of antibodies,
hormones & enzymes.
Recent studies have shown that
Lysine may be effective against herpes
by improving the balance of nutrients
that reduce viral growth.
A deficiency may result in tiredness,
inability to concentrate, irritability,
bloodshot eyes, retarded growth, hair
loss ,anemia & reproductive problems
METHIONINE (Essential Amino
Acid)
• supplier of sulfur which
prevents disorders of the
hair, skin and nails;
• helps lower cholesterol levels
by increasing the liver's
production of lecithin;
• reduces liver fat and protects
the kidneys;
• reduces bladder irritation;
• influences hair follicles and
promotes hair growth.
Primary Structure of a
Protein
•
The primary structure of a
protein is its amino acid
sequence, formed when a
peptide bond joins the
carboxyl group (one Carbon
atom, two Oxygen atoms, and
a Hydrogen atom) of one
amino acid to the amino group
(N) of another. A long chain
forms from many amino acids,
with one molecule of water
given off with the formation of
each peptide "link."
Secondary, Tertiary, and Quaternary Structure of a Protein
Interactions between the molecules that make up a protein cause the
coiled polypeptide chain (left) to fold into a three-dimensional structure
(center) which may join others to form a large, complex protein (right).
Protein Structure of a
Microtubule
• Microtubules are tiny hollow tubes
that make up cilia and flagella.
• in the cell wall of some eukaryotic
organisms.
• Forming the walls of the tube are
two types of globular protein
subunits, alpha and beta tubulin,
that come together to form a
compound called a dimer.
• The dimers self-assemble, coiling
to form a tube of the required
length. Inside each cilium (short)
or
• flagellum (long), nine pairs of
microtubules encircle a tenth,
central pair.
Nigerian Children Suffering
from Malnutrition
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Due to climate, drought, poor
agricultural planning, political
instability and ineffectiveness,
and the mismanagement of
natural resources, there are
millions of starving people
throughout the world.
It is estimated that each year
between 5 and 20 million
people die of starvation or
from diseases resulting from
malnutrition.
Most of them, like these
Nigerians, are children.
Carl Purcell/Science Source/Photo
Researchers, Inc.
Two of eight calves cloned from cells obtained
from one adult cow at Kinki University in Nara,
Japan. (1998.)
How are genes linked to disease?
• Many, if not most, diseases have their
roots in our genes.
• Genes - through the proteins they
encode - determine how efficiently we
process foods, how effectively we
detoxify poisons, and how we respond
to infections.
• More than 4,000 diseases are thought
to stem from mutated genes inherited
from one's mother and/or father.
• Common disorders such as heart
disease and most cancers arise from a
complex interplay among multiple
genes and between genes and factors in
the environment.
Correcting Genetic
Diseases
• Gene therapy may someday
be able to cure hereditary
diseases,
• such as hemophilia and
cystic fibrosis, which are
caused by missing or
defective genes.
• In one type of gene therapy,
genetically engineered
viruses are used to insert
new, functioning genes into
the cells of people who are
unable to produce certain
hormones or proteins
necessary for the body to
function normally.
Atkins diet
http://content.health.msn.com/content/article/3220.136
• By restricting carbohydrates, the body goes
into a state of ketosis, Atkins reasons,
whereby it burns its own fat for fuel.
• A person in ketosis is getting energy from
ketones, little carbon fragments that are the
fuel created by the breakdown of fat stores.
• When the body is in ketosis, you tend to feel
less hungry, and thus you're likely to eat less
than you might otherwise.
• However, ketosis can also cause a variety of
unpleasant effects.
What are Ketone bodies used for?
http://www.bestlowcarbs.com/article1067.html
• Brain fuel. The major role of ketone bodies is
to supply an alternative (to glucose) fuel for
the brain in situations where there are little or
no carbohydrates available with food.
• Building blocks for brain tissue.
• Ketone bodies are precursors for the essential
substance (acetyl-CoA) required in the
synthesis of lipid (myelin) in the neural cells.
What do you think?
• Atkins' theories remain unproven, and most
experts are concerned that Atkins' highprotein, high-fat diet can cause a host of
problems, particularly for the large segment
of the population that is at risk for heart
disease.
• What's more, the plan doesn't permit a high
intake of fruits and vegetables,
recommended by most nutrition experts
because of the numerous documented
health benefits from these foods.