Proteins are large molecules.
They are non actually soluble, rather they form colloids
- colloids are well-nigh 500nm, which is larger than particles inwards solution, but smaller than particles inwards suspension
- colloids be inwards a "sol-gel state", whereby sometimes they look to move liquid in addition to at other times they are jelly-like (much of the textile inwards cytoplasm is colloid)
Proteins contain: C, H, O in addition to N, sometimes due south in addition to P
There are an almost limitless divulge of proteins, which vary betwixt species in addition to are oftentimes species-specific (fajlagosok). They produce upwards one's take away heed the characteristics of a species.
Types of Proteins
a. Structural proteins - these form the organism. eg. hair, nails, feathers, etc.
b. Physiological proteins - these behave out functions, examples include:
-enzymes (biocatalysts)
-carrier molecules (szállítómolekulák)
- pigments (eg. diverse colouring molecules inwards pare in addition to eyes, haemoglobin inwards ruby blood cells)
- hormones (chemical messengers)
- contractile textile inwards muscles
- antibodies (disease protection)
** Proteins are rarely stored (only inwards seeds in addition to eggs). Proteins are simply broken downwards for liberate energy if a living organism is starving.
PROTEIN STRUCTURE
- a poly peptide is a polymer. Its monomers are called amino acids.
Image from http://api.ning.com/files/xO6ybWgUbfFlk7GUXm9d8dfR--U-fUdPOJEtDzVGgDY_/aminoacidstruc.jpg
- roughly amino acids are basic, others are neutral - this depends on the variable group
- roughly amino acids are polar in addition to others are apolar - this depends on the variable group
-amino acids are soluble inwards water, where they shape dipolar ions (zwitterion = ikerion), this way they accept BOTH acid-base properties, in addition to so they accept practiced buffering capacity.
Synthesis of polypeptides
- amino acids attach to each other past times condensation to shape covalent peptide bonds
ii amino acids condense to shape a dipeptide, iii shape a tripeptide and many joined together shape a polypeptide.
Formation of a dipeptide Image from:http://www.tutorvista.com/content/chemistry/chemistry-iv/biomolecules/chemical-properties--amino-acids.php
- if to a greater extent than than 100 amino acids attach together it is considered a protein
- polypeptides (and proteins) are broken downwards past times hydrolysis
*both condensation in addition to hydrolysis postulate enzymes to occur.
Structure
Primary structure: this is the divulge in addition to sequence of the amino acids.
*Insulin was the outset poly peptide to accept its primary construction determined past times a researcher named Fred Sanger
Secondary structure: This type of construction is created past times H-bonds forming betwixt amino acid monomers
Alpha helix (eg. keratin - a major ingredient of pilus in addition to skin)
Image from http://www.bio.miami.edu/ cmallery/150/protein/alpha-helix.jpg
Beta-pleated sheet (eg. silk protein)
Image from http://student.ccbcmd.edu/courses/bio141/lecguide/unit3/viruses/images/betasheet.jpg
-both structures tin move constitute inwards a unmarried protein.
Tertiary structure: This is the secondary construction folded inwards 3-dimensional space.
-usually forms globular shapes
-bonded past times S-bridges (requires the amino acid cysteine), ionic bonds, H-bonds in addition to van der Waals forces
Image from http://lectures.molgen.mpg.de/ProteinStructure/Levels/tertiary.gif
Quaternary structure: A poly peptide has fourth construction if it is formed of ii or to a greater extent than subunits (polypeptides). They are held together past times diverse forces including hydrophobic interactions, H-bonds in addition to ionic bonds.
eg. Haemoglobin
Image from http://www.theironfiles.co.uk/images/Haemoglobin_Structure.jpg
Proteins tin farther move catagorized as simple or complex. A uncomplicated poly peptide contains simply amino acids, complex proteins oftentimes include other elements, such equally the Fe containing haeme molecule constitute inwards haemoglobin (above).
Protein Stability in addition to Denaturation
H5N1 poly peptide volition move stable (maintain its shape in addition to function) if the surround it is inwards is appropriate. The most mutual environmental factors that volition campaign a poly peptide to denature (lose its shape and/or function) are temperature in addition to pH levels. Some proteins accept a broad arrive at of tolerance (can role at 4C in addition to at 40C), acre others accept a real narrow range. This is a protein-specific characteristic. An instance of poly peptide denaturation is when nosotros laid upwards an egg. The white of the egg is almost alone made of the poly peptide albumin. At room temperature it is a clear liquid. If nosotros growth the temperature, the poly peptide starts to denature (lose its shape in addition to so role too) in addition to it move enterprise in addition to white. Denaturation occurs because the bonds betwixt the amino acids are broken.
Sometimes denaturation is permanent (like cooking an egg), other times it tin move reversible.
They are non actually soluble, rather they form colloids
- colloids are well-nigh 500nm, which is larger than particles inwards solution, but smaller than particles inwards suspension
- colloids be inwards a "sol-gel state", whereby sometimes they look to move liquid in addition to at other times they are jelly-like (much of the textile inwards cytoplasm is colloid)
Proteins contain: C, H, O in addition to N, sometimes due south in addition to P
There are an almost limitless divulge of proteins, which vary betwixt species in addition to are oftentimes species-specific (fajlagosok). They produce upwards one's take away heed the characteristics of a species.
Types of Proteins
a. Structural proteins - these form the organism. eg. hair, nails, feathers, etc.
b. Physiological proteins - these behave out functions, examples include:
-enzymes (biocatalysts)
-carrier molecules (szállítómolekulák)
- pigments (eg. diverse colouring molecules inwards pare in addition to eyes, haemoglobin inwards ruby blood cells)
- hormones (chemical messengers)
- contractile textile inwards muscles
- antibodies (disease protection)
** Proteins are rarely stored (only inwards seeds in addition to eggs). Proteins are simply broken downwards for liberate energy if a living organism is starving.
PROTEIN STRUCTURE
- a poly peptide is a polymer. Its monomers are called amino acids.
Image from http://api.ning.com/files/xO6ybWgUbfFlk7GUXm9d8dfR--U-fUdPOJEtDzVGgDY_/aminoacidstruc.jpg
- roughly amino acids are basic, others are neutral - this depends on the variable group
- roughly amino acids are polar in addition to others are apolar - this depends on the variable group
-amino acids are soluble inwards water, where they shape dipolar ions (zwitterion = ikerion), this way they accept BOTH acid-base properties, in addition to so they accept practiced buffering capacity.
Synthesis of polypeptides
- amino acids attach to each other past times condensation to shape covalent peptide bonds
ii amino acids condense to shape a dipeptide, iii shape a tripeptide and many joined together shape a polypeptide.
- if to a greater extent than than 100 amino acids attach together it is considered a protein
- polypeptides (and proteins) are broken downwards past times hydrolysis
*both condensation in addition to hydrolysis postulate enzymes to occur.
Structure
Primary structure: this is the divulge in addition to sequence of the amino acids.
*Insulin was the outset poly peptide to accept its primary construction determined past times a researcher named Fred Sanger
Secondary structure: This type of construction is created past times H-bonds forming betwixt amino acid monomers
Alpha helix (eg. keratin - a major ingredient of pilus in addition to skin)
Image from http://www.bio.miami.edu/ cmallery/150/protein/alpha-helix.jpg
Beta-pleated sheet (eg. silk protein)
Image from http://student.ccbcmd.edu/courses/bio141/lecguide/unit3/viruses/images/betasheet.jpg
-both structures tin move constitute inwards a unmarried protein.
Tertiary structure: This is the secondary construction folded inwards 3-dimensional space.
-usually forms globular shapes
-bonded past times S-bridges (requires the amino acid cysteine), ionic bonds, H-bonds in addition to van der Waals forces
Image from http://lectures.molgen.mpg.de/ProteinStructure/Levels/tertiary.gif
Quaternary structure: A poly peptide has fourth construction if it is formed of ii or to a greater extent than subunits (polypeptides). They are held together past times diverse forces including hydrophobic interactions, H-bonds in addition to ionic bonds.
eg. Haemoglobin
Image from http://www.theironfiles.co.uk/images/Haemoglobin_Structure.jpg
Proteins tin farther move catagorized as simple or complex. A uncomplicated poly peptide contains simply amino acids, complex proteins oftentimes include other elements, such equally the Fe containing haeme molecule constitute inwards haemoglobin (above).
Protein Stability in addition to Denaturation
H5N1 poly peptide volition move stable (maintain its shape in addition to function) if the surround it is inwards is appropriate. The most mutual environmental factors that volition campaign a poly peptide to denature (lose its shape and/or function) are temperature in addition to pH levels. Some proteins accept a broad arrive at of tolerance (can role at 4C in addition to at 40C), acre others accept a real narrow range. This is a protein-specific characteristic. An instance of poly peptide denaturation is when nosotros laid upwards an egg. The white of the egg is almost alone made of the poly peptide albumin. At room temperature it is a clear liquid. If nosotros growth the temperature, the poly peptide starts to denature (lose its shape in addition to so role too) in addition to it move enterprise in addition to white. Denaturation occurs because the bonds betwixt the amino acids are broken.
Sometimes denaturation is permanent (like cooking an egg), other times it tin move reversible.
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