Term
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Definition
carbohydrates, nucleic acids, proteins, and lipids. Includes: C, H, O, N, S, Na, P,
K, Mg, Ca, Fe |
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Term
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Definition
| Co, Cu, Mn, Mo, Ni, Se, W, V, Zn; used as enzyme cofactors |
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Definition
| something that must be associated with a specific enzyme for the enzyme to function properly |
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Definition
| uses CO2 as sole C source; “self feeders” |
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Term
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Definition
uses several to many (different) preformed organic
carbon molecules, e.g., glucose, as C source (majority
of microorganisms) |
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Term
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Definition
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Definition
| uses oxidized organic compounds for energy |
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Definition
| reduced inorganic compounds are the electron source |
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Term
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Definition
| reduced organic compounds are the electron source |
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Term
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Definition
- organisms that cannot synthesize growth factors de novo
- must have access to organic compounds such as:
- amino acids (proteins, peptidoglycan)
- purines/pyrimidines (nucleotides, nucleic acids),
- vitamins (cofactors for enzyme catalysts)
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Term
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Definition
| any substance that is necessary for growth of a cell |
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Term
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Definition
- A substance structurally similar to a growth factor that could be incorporated into a cellular pathway resulting in inhibition of the pathway.
- ex. nucleotide analog would inhibit genome replication
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Term
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Definition
the synthesis of complex molecules from simple molecules such as sugars or amino acids
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Term
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Definition
| a selective medium that contains the dye, methylene blue, which selectively inhibits various Gram-positive bacteria, and therefore this medium is used to selectively culture Gram-negative bacteria. |
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Term
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Definition
| a small tube that captures gas produced by bacteria in a medium |
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Term
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Definition
| a population derived from a single cell |
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Term
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Definition
| Converting atmospheric N2 to nitrogen compounds such as ammonia and nitrate |
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Term
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Definition
| the complete killing or removal of all viable organisms |
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Term
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Definition
moist heat sterilization, using steam under high pressure (15 lb/in2), to reach and maintain a temperature of 121°C for ~15 min that is sufficient to kill bacterial endospores. High temperature, not the pressure, kills the microbe. Must
extend time if heat penetration of the object is slow. |
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Term
| what are the functions of vitamins in the cell? |
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Definition
- Growth factors with complex organic structures and serve as (precursors of) coenzymes or cofactors that work at the active site of important proteins, e.g., metabolic enzymes.
- As catalysts, they are needed in low quantities within the cell. Analog molecules with similar structure but lacking in catalytic activity may be competitive inhibitors and hence have antimicrobial activity.
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Term
| para-amino benzoic acid (PABA) |
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Definition
| common precurser in nucleotide synthesis |
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Term
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Definition
| Niacin is a precursor to NADH, NAD, NAD+, and NADP |
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Term
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Definition
| micronutrients used as enzyme cofactors |
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Term
| defined (synthetic) medium |
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Definition
| Synthetic medium in which all required components are known |
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Term
| undefined (complex) medium |
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Definition
contains some ingredients of undefined chemical
composition, e.g., peptone, meat extract, yeast
extract |
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Term
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Definition
| contains all essential nutrients, even those normally synthesized by the bacteria |
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Term
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Definition
| contains the minimum set of nutrients for a specific bacterium to grow |
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Term
agar
(what concentration is it most commonly used) |
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Definition
a red algal polysaccharide used to culture bacteria
1.5% |
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Term
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Definition
- contains substances that selectively inhibit the growth of certain microorganisms while allowing others to grow.
- Example: EMB agar contains the dye, methylene blue, which selectively
inhibits various Gram-positive bacteria, and therefore this medium is used to
selectively culture Gram-negative bacteria.
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Term
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Definition
- designed to differentiate whether certain chemical reactions occur (+ or -?) during growth of the microorganism.
- Example: a medium containing a pH indicator that changes color at certain pH. This medium would differentiate organisms that do or do not produce acid from fermentation of a sugar.
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Term
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Definition
| a technique used to transfer bacteria without contaminating the sample or the growth medium |
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Term
| 4 methods of isolating pure cultures of bacteria |
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Definition
- Streak plate
- Agar shake tube
- successive dilutions of cells in molten agar;
colonies form embedded in agar
(works well for anaerobes)
- pour plate
- add bacteria to plate, then pour liquid agar over bacteria. Incubate and the surface colonies will be pure isolated colonies
- spread plate techniques
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Term
| Most Probable Number (MPN) method for estimating bacterial counts in samples |
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Definition
1. Start with enrichment culture of sample to be tested
2. Make serial dilutions into fresh sterile medium
3. The highest dilution that shows growth is assumed to
have contained 1-10 cells
4. No growth in 10-5 dilution; MPN = 104 – 105 (1-10 x 104) per gram of sample |
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