Microbiology

By Prof Moses Joloba Basic Characteristics Properties (Actinomyces israelii) CAMP Negative (-ve) Capsule Non-Capsulated Catalase Negative (-ve) Flagella Negative (-ve) Gelatin Hydrolysis Negative (-ve) Gram Staining Positive (+ve) H2S Positive (+ve) Hemolysis Negative (-ve) Indole Negative (-ve) Motility Non-Motile MR (Methyl Red) Positive (+ve) Nitrate Reduction Positive (+ve) OF (Oxidative-Fermentative) Anaerobic Pigment Negative (-ve) Shape … Read more

By Prof Moses Joloba Basic Characteristics Properties (Bacillus subtilis) Catalase Positive (+ve) Citrate Positive (+ve) Flagella Flagellated Gas Negative (-ve) Gelatin Hydrolysis Positive (+ve) Gram Staining Gram Positive (+ve) Indole Negative (-ve) Motility Positive (+ve) MR (Methyl Red) Negative (-ve) Nitrate Reduction Positive (+ve) Oxidase Variable Pigment Negative (-ve) Shape Rods Spore Positive (+ve) Urease … Read more

By Prof Moses Joloba Basic Characteristics Properties (Alcaligenes faecalis subsp. faecalis) Bromocresol purple milk Alkaline reaction Capsule Negative (-ve) Catalase Positive (+ve) Citrate Positive (+ve) Flagella Positive (+ve) Gelatin Hydrolysis Negative (-ve) Gram Staining Gram-negative (-ve) Growth in 7% NaCl Positive (+ve) H2S Negative (-ve) Hemolysis Positive (+ve) Indole Negative (-ve) Motility Positive (+ve) Nitrate Reduction … Read more

By Prof Moses Joloba Basic Characteristics Properties (Aeromonas caviae) Catalase Positive (+ve) Citrate Positive (+ve) Flagella Variable (+/-) Gas Negative (-ve) Gelatin Hydrolysis Positive (+ve) Gram Staining Gram negative Growth in KCN Positive (+ve) Growth in 0% NaCl Positive (+ve) Growth in 3% NaCl Positive (+ve) H2S Negative (-ve) Hemolysis Variable (+/-) Indole Positive (+ve) … Read more

By Prof Walter Jaoko Introduction The nitrate reduction test is a qualitative procedure for determining the ability of bacteria to reduce nitrate. In the reaction, nitrate is reduced to nitrite, which may then be further reduced to nitrogen gas or ammonia.Other uses of Nitrate Reduction Tests are:  Differentiating Mycobacterium species. Identifying species of Neisseria and separating them from Moraxella and Kingella species. The nitrate … Read more

By Prof Walter Jaoko Introduction Acid-Fast (AF) is an important special staining technique used in the histology laboratory. It is a differential staining techniques which was first developed by Ziehl and later on modified by Neelsen 1883. This method is used for those microorganisms which are not staining by simple or Gram staining method, particularly the member of … Read more

By Prof Walter Jaoko Introduction DNA hydrolysis test or Deoxyribonuclease (DNase) test is used to determine the ability of an organism to hydrolyze DNA and utilize it as a source of carbon and energy for growth. In this regard, Deoxyribonuclease test medium (DNase agar) prepared according to the formula of Jeffries, Holtman and Guse, is … Read more

By Prof Walter Jaoko Introduction Oxidase test is most helpful in screening colonies suspected of being one of the Enterobacteriaceae (all negative) and in identifying colonies suspected of belonging to other genera such as Aeromonas, Pseudomonas, Neisseria, Campylobacter, and Pasteurella (positive). Oxidase test uses disks impregnated with a reagent such as N,N,N′,N′-tetramethyl-p-phenylenediamine (TMPD) or N,N-dimethyl-p-phenylenediamine (DMPD), which is also a redox indicator. The reagent is a dark-blue … Read more

By Prof Walter Jaoko Objectives To determine the ability of the organism to hydrolyse lipid. To identify bacteria capable of producing the exoenzyme lipase. Principle Lipids generally are nonpolar molecules that do not dissolve well in water.  Fats are one type of lipids that are large polymers of fatty acids and glycerol that are too … Read more