Bacteriologist Interview Preparation Guide

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When answering this question keep focused on what the company can offer you in the long term so the interviewer knows that you are going to stick around for awhile. Tell the interviewer that you can see this as a long term career and that you are happy to learn the job and that you are also keen to pursue further education and even an additional degree to achieve your goals.

An often fatal and infectious disease, caused by ingestion or inhalation of spores of Bacillus anthracis, which are normally found in soil. It is acquired by humans through contaminated wool or animal products or by inhalation of airborne spores

Quaternary ammonium compounds are positively charged polyatomic ions, which concentrate at the cell surface and alter the physical and chemical properties of the membrane, thus killing the cefl. Examples inlcude Benzalkonium chloride and Cetrimonium bromide.

The two methods namely Kinyoun’s and Gabbetts dont involve heating of slides, hence called cold methods. Heating is substituted by increased concentration of phenol and prolonging the duration of staining. Kinyoun’s method is favoured for detection of Cryptosporidium oocysts in fecal samples. Gabbetts method has decolourizer and counterstain in one solution.

LoetTler’s methylene blue solution treated with Potassium hydroxide turns into Polychrome methylene blue after prolonged storage with shaking. Used in McFadyean’s reaction for Bacillus anthracis in blood films and demonstration of metachromatic granules of Corynebacterium diphtheriae.

Preparing for this question requires a little bit of self-awareness and strategy. You don't want to share that you have trouble working with difficult people or that you struggle with the details, as those are key aspects of your role. What you do want to focus on is a weakness that you could possibly turn into a strength or share something that would not be detrimental to your role that you are working on improving.

Refers to organisms that survive in the absence of oxygen (anearobic organisms), the absence of molecular oxygen, processes occurring in the absence of oxygen like anearobic respiration.

Agarose is obtained from seaweed and is used as a resolving medium in electrophoresis. It consists of non-sulfated linear polymer, which contains D-galactose and 3:6-anhydro-L-galactose alternately.

Cell wall theory: Cell wall of Gram positive bacteria are 40 times thicker than those of Gram negative cells, hence they are thought to help retain the dye-iodine complex.
Lipid Content Theory: Cell envelope of Gram negative bacteria contains an additional membrane (outer membrane). hence containing more lipids than Gram positive bacteria. Acetone or alcohol dissolves the lipid thus forming large pores in Gram negative bacteria through which the dye-iodine complex leaks out. Alcohol/acetone dehydrates Gram positive bacteria shrinking the cell wall and the closing the pores.
Magnesium Ribonucleate Theory: A compound of magnesium ribonucleate and basic protein concentrated at the cell membrane helps Gram positive bacteria retain the primary dye. Gram negative bacteria do not possess this substance.
Cytoplasmic pH Theory: The cytoplasm of Gram positive bacteria are said to be more acidic (2) than those of Gram negative ones (3). Hence the dye is said to bind with more affinity to Gram positive cells.

These are Gram positive, nonmotile, nonsporing, noncapsulated filaments that break into bacillary and coccoid elements. They resemble fungi, and most are free living, particularly in soil.