You isolate an organism from a water sample and test it with a catalase test and grow it in thioglycollate medium. The results showed bubbling after the addition of hydrogen peroxide and a band of growth at the top of the thioglycollate tube. What is the most likely oxygen classification of your organism

The most likely oxygen classification is OBLIGATE AEROBIC ORGANISM.

Explanation: Most medically important bacteria can be grown artificially in the laboratory provided the atmospheric conditions and temperature are correct and the culture medium used contains the required nutrients.

The thioglycollate medium is used to differentiate oxygen requirements in an isolated organisms. While catalase test is used to differentiate catalase producing from non-catalase producing organisms.

Differences in the effect of oxygen on bacterial growth provide a further way of classifying bacteria:

● OBLIGATE AEROBES, which require free oxygen to grow,

● obligate anaerobes, which are unable to grow in free oxygen,

● facultative anaerobes, which can grow in conditions in which oxygen is present or absent,

● microaerophiles which grow best in conditions of reduced oxygen concentration.

The most likely oxygen classification is OBLIGATE AEROBIC ORGANISM because from the result of the test carried out on the isolated organisms,

--> The organism is catalase positive as it was able to breakdown hydrogen peroxide to oxygen and water( bubbling after the addition of hydrogen peroxide confirmed it as positive). Catalase is an enzyme produced by all aerobic organisms.

--> while in the thioglycollate medium the organism grew at the top of the test tube in order to absorb maximal amount of oxygen.