Basic Chemistry and Microbiology

Review of Basic Chemistry

smallest basic particle is the atom› Electrons- negatively charged› Protons- positively charged in nucleus› Neutrons- uncharged in nucleus

when electrons are lost or gained, a charge occurs

substances containing only one kind of atom are called elements

approximately 20 elements are found in all living things

carbon, hydrogen, oxygen, and nitrogen make up 97%

the other 16 are called trace elements

Molecules are when two or more atoms are joined together (Ex: O2, CO2 )

Compounds and Solutions

Two or more atoms or molecules joined in a definite proportion by weight is called a compound

Compounds have different characteristics from elements they are made from

Represented by a formula

Compounds and Solutions

Two or more atoms or molecules joined in a definite proportion by weight is called a compound

Compounds have different characteristics from elements they are made from

Represented by a formula

Compounds and Solutions

Types of Compounds› Inorganic

Do not contain carbon Often has a metal as a positive ion

› Organic Found in living things Always contain carbon When with hydrogen they are called

hydrocarbons (usually gases) When with other carbons, they bond in

chains

Compounds and Solutions

Solutions› Chemical process take place in solutions› A solution is when one substance dissolves

into another› The solute is dissolved into the solvent› If it dissolves it is soluble, if not, insoluble

› Note: in microbiology, a tincture is alcohol and some other substance

Carbohydrates

All have carbon (C), hydrogen (H), and oxygen (O)

Occur in ration of 1:2:1

Carbohydrates

Monosaccharides› Single or simple sugars› Glucose, fructose, galactose› They are isomers (same formula, but

different arrangement)

Carbohydrates

Glucose (also known as dextrose)› Carried in bloodstream› Combines with oxygen (oxidation) and

produces adenosine triphosphate (ATP) Fructose (found in fruits and honey)

› Sweetest of all monosaccharides Galactose

› Found in small amounts in agar, flaxseed, and milk

NOTE: “ose” means sugar

Carbohydrates

Disaccharides › Known as a double sugar› Examples: sucrose(table sugar), lactose

(milk sugar)and maltose (malt sugar) Chemical reaction to join:

› Dehydration synthesis (opposite to break apart is hydrolysis)

Dehydration Synthesis

+ = Disaccharide

Hydrolysis

Disaccharide + =

Carbohydrates

Oligosaccharides› Form chains called polymers› Small chains with only 2-10 monosaccharides› Ex: insulin

Polysaccharides› Large, complex molecules› Made of hundreds of thousands of glucose› Have very long polymer chains› Ex: starch, cellulose, and glycogen

Carbohydrates

https://www.youtube.com/watch?v=M6ZLDJluj6I

http://www.khanacademy.org/partner-content/crash-course1/crash-course-biology/v/crash-course-biology-103

Lipids

Examples are fats, oils, and waxes Like carbs, they have carbon, hydrogen,

and oxygen, but much less oxygen Fats are solid and oils are liquid at room

temperature Better sources of energy than

carbohydrates (yield more energy) but are harder to oxidize

Three groups: simple lipids, compound lipids, and derived lipids

Lipids

Simple Lipids (triacylycerol or triglyceride) contain one glycerol molecule and

three fatty acids held together by ester linkages

Formed by dehydration synthesis

Lipids

Simple Lipids Saturated (when all carbon bonds are

single and saturated with hydrogen)› Can block arteries› Difficult to break up› Raises cholesterol› Solid at room temperature

Lipids

Simple Lipids Unsaturated (when two or more hydrogen

bonds are replaced with double bonds between carbon atoms)› Liquid at room temperature› Monounsaturated (lacks 2 hydrogen bonds)

or Polyunsaturated (lacks 8 or more hydrogen bonds forming 4 or more double bonds)

› Lowers Cholesterol› Easier to break up

Lipids

Trans Fats› Unsaturated fat but act like a saturated fat› Has trans arrangement in bonding- the

hydrogens are on opposite sides of the double bond.

› Typical man-made

Lipids

https://www.youtube.com/watch?v=3xF_LK9pnL0

https://www.youtube.com/watch?v=VGHD9e3yRIU

Lipids

Compund lipids- lipids which contain an inorganic or organic group in addition to fatty acids and glycerol. › Phosphpholipids- Lipids containing a

phosphate group. A phospholipid molecule has a strongly nonpolar and hydrophobic (water insoluble) tail region represented by fatty acid chains and a strongly polar or hydrophilic (water soluble) head region

represented by the phosphate group.

Lipids

› Glycolipids- These are lipids containing a carbohydrate group, usually galactose. They are found in the nerve cell membranes especially in the myelin sheath.

Lipids

› Lipoproteins- These are lipids, usually phospho-lipids which contain a protein molecule. They occur in the cell membrane. They are also found in milk and egg yolk

Lipids Derived Lipids (Sterols)

› Contain only carbon, hydrogen, and oxygen› Include steroids found in male and female

hormones, Vitamin D, cholesterol, and fat soluble vitamins A, E, and K

› Classified as lipids only because they are soluble in fat solvents

› These are lipids that do not have a straight chain. They are composed of four fused carbon rings and a long hydrocarbon side chain.

Lipids

Derived Lipids

Proteins

Contain hydrogen, oxygen, and nitrogen and most times phosphorus and sulfur

Found in every part of living cells Coat viruses In binding and structural components

like fingernails, hair, ligaments, muscles, etc.

Made of AMINO ACIDS

Proteins

Structure of Amino AcidPosition 1 is carbon, Position 2 is amino group (NH2), Position 3 is hydrogen atom, Position 4 is a carboxyl group (COOH), and Position 5 is variable (R)

Proteins

Ex: Glycine (H is in R group)

Large protein molecules are constructed from any number and sequence of amino acids (can number from 300 to thousands)

Proteins

Amino acids linked by dehydration synthesis (C-N) (bond between carboxyl group of one amino acid and amino group of next amino acid). Called a PEPTIDE BOND and a series of linkages is called a POLYPEPTIDE

THIS IS CALLED A PROTEIN

Proteins

Structure› Primary- straight chain› Secondary- helix› Tertiary- twisted and folded› Quaternary- two or more polypeptide

chains are bonded together

Proteins

http://www.youtube.com/watch?v=lijQ3a8yUYQ

https://www.youtube.com/watch?v=2Jgb_DpaQhM

Proteins

Functions:

Enzymes - proteins that allow chemical reactions to occur in living things Antibodies – proteins that protect the body from

infection Structure – cytoskeleton, hair, nails, muscles, spider

web, silk, feathers ,horns, hooves etc…. Hormones – chemical messengers Cell membrane – proteins can act as channels through

the cell membrane - receptor proteins found on membrane transmit signals to the inside of cells

Hemoglobin – protein found in blood that carries oxygen

Proteins

Proteins

Denatured proteins are proteins that lose their shape - if they lose their shape, they also lose their - What can cause a protein to become denatured? Exposure to: Strong Acid Strong Base Heat Organic solvent: Alcohol or

Acetone - Denatured proteins can lose quaternary, tertiary

and secondary structure - Primary Structure is left untouched

Proteins (enzymes)

Specialized proteins Help provide energy to cell at just the

right moment and at just the right speed

Also known as organic catalysts Highly specific Very large and complex

Proteins (enzymes)

Made of either all protein or part protein (apoenzyme)attached to a non-protein part (coenzyme)

Coenzymes could be calcium, iron, magnesium, copper, or vitamins like C and B-complex

Proteins (enzymes)

The localized site on the enzyme molecule is called the active site

Each enzyme has its own pattern on the active site (no 2 alike)

An enzyme reacts with a reactant whose molecular pattern fits the enzyme’s molecular pattern.

The molecule that the enzyme reacts with is called a SUBSTRATE molecule

Proteins (enzymes)

Lock and key model

Proteins (enzymes)

Temporary physical binding called

Enzyme-Substrate Complex

Proteins (enzymes)

Enzymes are proteins and if they are exposed to extremes of temp or pH lose their shape - if a protein loses its shape, it loses its

function - a protein that loses its shape is said to

be denatured - if an enzyme is denatured, substrate

cannot enter the active site

Proteins (enzymes)

extreme temperatures or pH

Proteins (enzymes)

Name usually ends in –ASE Added to stem word taken from

substrate Examples:

› Lactase……lactose› Lipase……...lipids› Maltase……maltose› Protease…...protein› Sucrase…….sucrose

Proteins (enzymes)

An example in microbiology:

Many bacteria have an enzyme that needs a compound called PABA (para-aminobenzoic acid). PABA helps bacteria make a vitamin called folic acid, which the bacteria need to grow.

Proteins (enzymes)

An example in microbiology:

When antibiotic sulfanilamide is given to the bacteria instead of PABA, the sulfanilamide molecules attach to active sites of bacteria and folic acid is not made.

Proteins (enzymes)

Nucleic Acids

Contain carbon, oxygen, hydrogen, nitrogen, and phosphorous

Two types- DNA and RNA

Nucleic Acids

DNA› Found in chromosomes and genes, plasma

membrane, mitochondria, and chloroplasts

› Consists of a phosphate group, deoxyribose sugar and one of four nitrogenous bases: adenine, thymine, cytosine, and guanine

Nucleic Acids

Nucleic Acids

RNA› Consists of a phosphate group (ribose

sugar), and any of the following nitrogenous bases: adenine, cytosine, guanine, and uracil

› Single stranded› Found in cytoplasm, nucleoli, and

ribosomes› Two kinds: mRNA and tRNA