NUTRITIONAL REQUIREMENTS OF MICROORGANISMS Flashcards
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
Agar could be? (3)
REMAINS SOLID AT USUAL INCUBATION TEMP
* NOT A NUTRIENT FOR MOST MCGS AND IS NOT METABOLIZED DURING
MICROBIAL GROWTH
(W/ DEMANDING NUTRITIONAL
REQUIREMENTS E.G. LACTOBACILLUS ACIDOPHILUS) OTHER
COMPOUNDS MAY BE ADDED (E.G. AMINO ACIDS &/OR VITAMINS)
WITH FASTIDIOUS ORGS
COMMONLY USED MEDIA (3)
NUTRIENT AGAR/BROTH, TGYA, PLATE COUNT
AGAR
IMITATE NORMAL HABITAT ( CHEMICALLY DEFINED- OR COMPLEX)
* DEPEND ON THE TYPE OF BACTERIA BASED ON NUTRITIONAL
REQUIREMENT
MEDIA FOR GROWTH OF BACTERIA
MANY ON UNCOMPLICATED MEDIA, OTHERS ON COMPLEX MEDIA
MEDIA FOR GROWTH OF FUNGI
LIVE ON DEAD ORGANIC MATTER part of media for growth of fungi
SAPROPHYTIC-
Examples of MEDIA FOR GROWTH OF FUNGI (3)
POTATO DEXTROSE AGAR, POTATO INFUSION AGAR , SABORAUD’S
AGAR,
Media for protozoa means (4)
- MANY HAVE NOT BEEN GROWN IN VITRO
- IF CAN BE GROWN IN VITRO REQUIRE A RANGE OF AMINO ACIDS &
VITAMINS PLUS CARBOHYDRATES - AMOEBAS IN PEPTONE BROTH
- SOME ON NUTRIENT BROTH OR WATER GELLED AGAR IF GIVEN BACTERIAL
CELLS TO INGEST
MEDIA FOR GROWTH OF ALGAE (3)
NEED LIGHT AND REQUIRE ONLY CO2, WATER AND INORGANIC
IONS
* SOME CAPABLE OF HETEROTROPHIC GROWTH IN THE DARK
(EUGLENA)
* FEW COMMERCIALLY AVAILABLE, STANDARDIZED PACKAGE MEDIA
MEDIA USED FOR CULTIVATING
MICROORGANIMS (4)
MEDIA FOR GROWTH OF BACTERIA
MEDIA FOR GROWTH OF FUNGI
MEDIA FOR GROWTH OF PROTOZOA
MEDIA FOR GROWTH OF ALGAE
SPECIAL- PURPOSE MEDIA (5)
SELECTIVE MEDIA
DIFFERENTIAL
ENRICHMENT
SELECTIVE/DIFFERENTIAL
MICROBIOLOGICAL ASSAY
DESIGNED TO ENHANCE THE GROWTH OF A
PARTICULAR KIND OF MICROORGANISMS OR SUPPRESS
THE GROWTH OF OTHER KINDS OF MCGS
CONTAINS INHIBITOR/S THAT SUPPRESS GROWTH OF
OTHER MCGS
SELECTIVE MEDIA
SELECTS FUNGI (W/ LOW
PH & HIGH GLUCOSE) selective example
SABOURAUD’S AGAR
ISOLATE SALMONELLA
FROM COMMON INHABITANTS OF INTESTINAL TRACT selective example
BRILLIANT GREEN AGAR
DIFFERENTIATE VARIOUS KINDS OF MCGS ON AN AGAR PLATE
Differential media
DIFFERENTIATES STREPTOCOCCUS PYOGENES (HEMOLYTIC)
FROM NONHEMOLYTIC BACTERIA FROM THE SAME SPECIMEN BY PRODUCING
CLEAR ZONES AROUND EACH COLONY differential example
BLOOD AGAR
DIFFERENTIATES FECAL-COLIFORM
E.COLI WITH NON-FECAL COLIFORM ENTEROBACTER AEROGENES
EOSIN METHYLENE BLUE AGAR (EMBA)
USEFUL IN PUBLIC HEALTH MICROBIOLOGY (E.G. DETERMINING WATER QUALITY,
FINDING THE CAUSE OF FOOD POISONING)
Selec/differential
INHIBITS GRAM + BACTERIA (DUE TO BILE SALTS &
CRYSTAL VIOLET) AND DIFFERENTIATES LACTOSE-FERMENTING GRAM - BACTERIA
FROM THOSE THAT DO NOT FERMENT selec/diffe example
MACCONKEY AGAR
Enrichment def 3
ENHANCES THE GROWTH OF MICROORGANISMS PRESENT ONLY IN
SMALL NUMBERS
* NO INHIBITORY SUBSTANCES PRESENT
* AFTER SERIES OF TRANSFER TO NEW MEDIA DESIRED SPECIES EMERGE
AS THE PREDOMINANT OR ENRICHED POPULATION
– ISOLATES PHENOLOXIDIZING BACTERIA FROM SOIL enrich example
AMMONIUM SALTS MEDIUM W/ PHENOL
Microbial assay (3)
- USED TO MEASURE THE CONCENTRATION OF
SUBSTANCES SUCH AS ANTIBIOTICS AND VITAMINS (ON
BLOOD SERUM, TISSUE FLUIDS, PHARMACEUTICAL
PRODUCTS, ANIMAL FEEDS, OTHER MATERIALS) - INVOLVES USE OF TEST ORGANISMS SUSCEPTIBLE TO
THE ANTIBIOTIC - MEASURED BY THE DEGREE OF GROWTH INHIBITION
FOR ANTIBIOTIC ASSAY
MUELLER –HINTON AGAR
