NUTRITIONAL REQUIREMENTS OF MICROORGANISMS Flashcards
(47 cards)
MAIN ELEMENTS FOR CELL GROWTH (5)
1.CARBON
2. NITROGEN
3. HYDROGEN
4. OXYGEN
5. SULFUR
6. PHOSPHORUS
2 MAJOR GROUPS OF ORGANISMS BASED ON CARBON REQUIREMENT
- AUTOTROPHS
- HETEROTROPHS
Give the nutritional classification of bacteria and other organism
Table
The bacteria grow near the bottom of the
spring pool and float to the top (by virtue of their gas
vesicles) when disturbed.
Blooms of purple sulfur bacteria.
Thiopedia
The filamentous cells twist together
to form thick streamers, and the white color is due to the
abundant elemental sulfur content of the cells.
Sulfur-oxidizing
bacteria
inorganic cpds as electron donor for cellular
respiration and CO2 as carbon source) are autotrophs.
chemolithotrophs
ARE NUTRIENT PREPARATIONS FOR THE
GROWTH OF MICROORGANISMS IN THE LABORATORY.
CULTURE MEDIA (SING. MEDIUM)
MUST PROVIDE THE ESSENTIAL CHEMICAL ELEMENTS FOR GROWTH OF
MCG’S
THE CHEMICAL COMPOUNDS ARE GROUPED AS FOLLOWS:
- NITROGEN SOURCES
- CARBON SOURCES
- ENERGY SOURCES
- MINERALS
- GROWTH FACTORS
2 TYPES OF CULTURE MEDIA
CHEMICALLY DEFINED
CHEMICALLY UNDEFINED OR COMPLEX
EXACT COMPOSITION IS KNOWN
CHEMICALLY DEFINED
Examples of chemically defined 2
E.G. GLUCOSE MINIMAL SALT AGAR
PREPARED FROM NATURAL PRODUCTS
CHEMICALLY UNDEFINED OR COMPLEX
Examples of chemically undefined or complex ket 4
NUTRIENT AGAR (NA), NUTRIENT BROTH (NB), COCONUT WATER AGAR (CWA),
TRYPTONE GLUCOSE YEAST EXTRACT AGAR (TGYA), PLATE COUNT AGAR (PCA), POTATO
DEXTROSE AGAR (PDA), ETC.
NATURAL PRODUCTS: (3)
MEAT EXTRACT
PEPTONE
YEAST EXTRACT
Meat extract example and meaning
E.G. BEEF EXTRACT (HYDROLYZED EXTRACT OF MEAT)
Peptone example and meaning
PROTEINS THAT HAVE BEEN PARTIALLY DEGRADED BY THE ENZYME
PROTEASE (E.G. MILK-CASEIN HYDROLYSATE, SOYBEAN-CASEIN HYDROLYSATE
Yeast extract ex and mean
CONTAINS- WATER-SOLUBLE VITAMINS TO ENHANCE MICROBIAL
GROWTH E.G. VITAMIN B
ALL ARE COMPLEX SUBSTANCES CONTAINING SUGARS, AMINO ACIDS, VITAMINS & SALTS;
THEIR EXACT COMPOSITION IS UNKNOWN.
T OR F
T
A COMPLEX POLYSACCHARIDE EXTRACTED FROM MARINE ALGAE,
SPECIFICALLY FROM RED SEAWEED (AGAROPHYTES)
Agar
2 POLYSACCHARIDES
AGAROSE (CA 70%) AND AGAROPECTIN (CA 30%)
CHIEF COMPONENTS in agar
D-GALACTOSE & 3,6-ANHYDRO-L-GALACTOSE
- IDEAL SOLIDIFYING AGENT BEC IT REMAINS MOLTEN & LIQUID AT
40-45*C after cooling from boiling point
MCG’S are not usually killed at 45C can be added into a liquid medium containing molten agar before it is poured to tubes or petri plate
T or F
T
