Tag: bacteria - friend and foe

Bacteria which directly convert atmospheric nitrogen into nitrogen compounds are called nitrogen fixing bacteria. They could be symbiotic or free- living like Rhizobium and Azotobacter respectively.
So answer is -'Nitrogen fixing bacteria'.

A chemoorganotroph is an organism, that obtains energy from the oxidation of reduced organic compounds. The list of compounds from which chemoorganotrophic organisms can generate energy and their sources of carbon is very long, making these microorganisms extremely versatile. Two mechanisms for energy conservation are known for chemoorganotrophs: fermentation and respiration.
So answer is - 'Chemoorganotrophs'.

Typhoid is a bacterial infection that is caused by the bacteria Salmonella typhi. Symptoms include high fever, diarrhea, vomiting, headache, abdominal pain. It is spread by food or water contaminated with the feces of an infected person. 

Denitrification is the biological conversion of nitrate to nitrogen gas, nitric oxide or nitrous oxide.  These compounds are gaseous compounds and are not readily available for microbial growth; therefore they are typically released to the atmosphere. Denitrifiers belong to several genera including Pseudomonas,Bacillus, Spirillum, Hyphomicrobium, Propionobacterium, Cornebacterium, Thiobacillus, and Alcaligenes. Biological denitrification is an anaerobic respiration reaction in which nitrate is reduced. Denitrifying bacteria are aerobic autotrophs or heterotrophs that can switch to anaerobic growth when nitrate is used as an electron acceptor.
 So, the answer is option C.

Enzyme nitrogenase, that catalyses nitrogen fixation is oxygen labile. Leguminous plant proteins called leghaemoglobin act as oxygen scavenger facilitating Rhizobium in fixing nitrogen.
So answer is- 'Oxygen removal'.

• Clostridium butylicum - lactic acid is a wrong match of a microbe and its industrial product because Clostridium butylicum forms butyric acid.
• So, the correct answer is 'butyric acid'.

There are basically two methods of pasteurization in use today- batch and continuous flow. In the batch process (batch pasteurizer), a large quantity of milk is held in a heated vat at 149$^{0}$F/65$^{0}$C for 30 minutes, followed by quick cooling to about 39$^{0}$F / 4$^{0}$C. In the continuous flow process (continuous flow pasteurizer) also known as HTST, for high temperature, short time, milk is held at 161$^{0}$F / 72$^{0}$C for at least 16 seconds. Before being chilled back to 39$^{0}$F / 4$^{0}$C. 

Microorganisms are used in brewing, wine-making, baking, pickling and other food-making processes. They are also used to control the fermentation process in the production of cultured dairy products such as yogurt and cheese. The cultures also provide flavour and aroma, and inhibit undesirable organisms. Microbes are used in the biological treatment of sewage and industrial waste effluents. Microbes are used in fermentation to produce ethanol.