MIP302 - Final Exam .

MIP302 - Final Exam thermophiles - Answerbacteria that live in environments with elevated temperatures (above 131°F) super/hyper thermophile - Answerbacteria that live in environments with extremely elevated temperatures (above 300°F) Differential Media - Answerallows for growth of bacteria, but differentiates bacteria based on some characteristic appearance on a media type Selective media - Answerallows for certain types of bacteria to grow (inhibits others) Aerobic bacteria - Answerrequire atmospheric oxygen microaerophilic bacteria - AnswerRequire atmospheric oxygen but at reduced levels facultative anaerobes - AnswerGrow with or without oxygen (better with oxygen) obligate anaerobe - Answergrow in absense of atmospheric oxygen Ambient air - AnswerNormal air candle jar - Answerreduced levels of O2, higher levels of CO2 GasPak - Answerreduced environment (devoid of O2) Redox indicators for Gaspak and Candle jar - AnswerRedox indicator methylene blue (blue when oxidized, white in reduced state) Catalase Test - AnswerTo see if bacteria produces enzyme catalase; add 3% H2O2 to a DRY smear of bacteria; produces bubbles=(+); delayed/no bubbles=(-) Oxidase Test - AnswerTo see if bacteria produces cytochrome oxidase (uses cytochrome C and cytocrhome oxidase in ETC); uses Oxidrop as reagent; blue/maroon=oxidized, (+); colorless= reduced, (-); 3 MIN PR Glucose Broth - AnswerTesting for glucose fermentation; Differential media (ability to ferment carb); phenol red indicator (yellow in acidic, red in basic); contains peptone and beef extract in PR broth; Durham tube put in tube to catch gas; yellow=(+); red=(-); 18-24 hours Nitrate Broth - AnswerDifferential media [ability to reduce nitrate (NO3) to nitrite (NO2)] using anaerobic resp.; Nitrate A and Nitrate B reagents (react w/ nitrite-- red); RESULTS: red during first round, (+) nitrate reductase, (-) nitrite reductase; Colorless during first round, inconclusive, add zinc; Red during second round (Nitrate A, B, and zinc) (-) for nitrate and nitrite reductase; Colorless during second round (+) nitrate and nitrite reductase; 48 HOURS MacConkey Agar - AnswerTo test for lactose fermentation of Gram (-) rods; differential media (lactose fermentation); selective media (grows Gram - enteric bacilli, inhibits Gram - cocci and Gram +); neutral red reagent (red in acidic, yellow in basic); contains peptone and beef extract; RESULTS: red/dark-pink colonies surrounded by zone of bile salt, strong lactose fermenter; colorless colonies, do not ferment lactose; if no growth, cannot make conclusions about lactose fermentation; 18-24 HOURS Phenylethyl Alcohol (PEA) Agar - AnswerTest for Gram (+) growth; Selective (selective component 1/4 phenylethyl OH); not as stringent as MacConkey; RESULTS: growth, most likely Gram (+) but have to do a Gram stain to check; 18-24 HOURS Blood Agar (BAP) - AnswerUsed to cultivate medically significant bacteria; all-purpose media; differential (ability to hemolyze red blood cells); includes TSA and sheep red blood cells; RESULTS: BETA, complete hemolysis, clear zone surrounding colonies; ALPHA, incomplete lysis, green-ish brown area surrounding colony; GAMMA, no lysis; Don't look at colony itself to determine results; 24 HOURS Pseudosel Agar (Cetrimide Agar) - AnswerUsed to isolate and identify Pseudomonas aeruginosa; Selective (P. aeruginosa can grow, all others inhibited bc of cetrimide); Differential (produce pyocyanin); can see under room lighting; RESULTS: blue/green colonies, positive result, P. aeruginosa; 18-24 HOURS Pseudomonas Agar F - AnswerUsed to differentiate bacteria based on ability to produce pigment fluorescein (differential); all-purpose medium; contains magnesium and potassium salts (enhance fluorescein production); should be visualized under UV, even tho can see green pigment in room lighting; RESULTS: glowing under UV, produces fluorescein, (+); 18-24 HOURS enteric bacteria - AnswerGram negative facultative anaerobic rods coliforms - AnswerGram negetaive rods that ferment lactose and produce gas, facultative anaerobes, and do not produce spores tryptophanase - Answerenzyme produced by bacteria that can use tyrptophan as a carbon source tryptophan - Answercatabolized into indole, pyruvic acid, and ammonia tryptone broth - Answermedium for indole test 48 - Answerindole test is incubated for __ hours Kovac's reagent - Answeradded to broth after incubation in indole test present - Answerif bacterium produces tryptophanase, indole will be ______ in the broth absent - Answerif bacterium does not produce tryptophanase, indole will be ______ in the broth red ring - Answerkovac's reagent reacts with the indole to produce a ___ ____ at the surface of the broth (if positive) negative - Answerif the bacterium has no color change after adding the Kovac's reagent, it is a _____ result for indole/tryptophanase production mixed acids - Answerif a bacteria ferments glucose, it may use a pathway that produces _____ ____ (MR) acetonin - Answerdiacetyl and 2,3-butanediol acetonin - Answerif a bacteria ferments glucose, it may use a pathway that produces _____, a neutral product (VP) Methyl red - Answerred when acidic, yellow when basic .