PUBH 1517 - (Chapter 6) The Proteins and Amino Acids

PUBH 1517 - (Chapter 6) The Proteins and Amino Acids -...

Info iconThis preview shows pages 1–17. Sign up to view the full content.

View Full Document Right Arrow Icon
Chapter 6 The Proteins and Amino Acids PUBH 2102
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Protein The human body contains 17% protein 1g protein = 4kcal Composed of carbon, hydrogen, oxygen, and nitrogen Arranged as amino acids Working proteins = enzymes, antibodies, transport vehicles, hormones, cellular “pumps,” oxygen carriers Structural proteins = tendons, ligaments, scars, the cores of bones and teeth, hair filaments, materials of nails
Background image of page 2
Amino Acids (AAs) = building blocks of Protein Amino acids in a strand of Pro are different from one another About 20 different AAs with 20 different side chains make up most of the proteins in living tissues Side chain gives identity to the AAs and make them differ in size, shape, and electrical charge
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 4
Essential Amino Acids (EAAs) = AAs that either cannot be made at all by the body or cannot be made in amounts sufficient to meet physiological needs Essential Amino Acids n = 9 Histidine Isoleucine Leucine Lysine Methionine Phenylalanine Threonine Tryptophan Valine
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
EAAs - continued EAAs can only be obtained from foods A non-essential AA. may become an essential AA in special circumstances For example: tyrosine (a non-essential AA) is made in the body from phenylalanine (EAA). If diet fails to provide enough phenylalanine (as in PKU) or cannot convert it to tyrosine, then tyrosine becomes a conditionally essential amino acid
Background image of page 6
Non-essential Amino Acids (dispensable AAs) Alanine Asparagine Cysteine Glutamine Proline Tyrosine Arginine Aspartic acid Glutamic acid Glycine Serine Non-essential AAs can be synthesized by the body via transamination or deamination
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
How do amino acids make proteins? Each amino acid is hooked onto the next A chemical bond, called a peptide bond , is formed between amine group end of one AA and the acid group end of the next Side chains bristle out from the backbone of the structure (giving the protein molecule its unique structure) Protein synthesis takes place in the cytosol and not in the cell nucleus.
Background image of page 8
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 10
Background image of page 11

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Variety of Proteins . . . Different shaped Proteins have different tasks Enzymes – act on other substances to chemically change them Globular proteins (some proteins of the blood) – water soluble Hollow – carry and store materials in interior Ropelike – give strength and elasticity to body parts
Background image of page 12
Amino Acid Sequences Specified by heredity Written into your genetic code Only one proper AA sequence for each protein; if wrong AA is inserted, the result may be disastrous to health (i.e. – sickle-cell disease)
Background image of page 13

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 14
Protein Turnover Proteins are constantly being degraded and synthesized and this process is called protein turnover Hormones that increase protein synthesis are insulin and growth hormone Protein degradation occurs in wasting conditions such as untreated AIDS
Background image of page 15

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Nutrients and Gene Expression Cells specialize in making only proteins typical of their cell types For example:
Background image of page 16
Image of page 17
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 54

PUBH 1517 - (Chapter 6) The Proteins and Amino Acids -...

This preview shows document pages 1 - 17. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online