An understanding of the nucleic acid molecules which include deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) important for us to understand the molecular and/or genetic basis of life. Nucleic acid molecules are found in all living organisms as the carriers of genetic materials from parent organisms to their offspring’s. With the exception of viruses (which […]
RIBONUCLEIC ACID (RNA) Read More »
Biotechnology, Molecular Microbiology
Proteins are a group of polypeptides that form a molecule of specific biological function; and they comprises mainly of amino acid sequences that are held together by a special type of covalent bonds known as peptide bonds. They are macromolecules that consist of long chains of amino acids held together in structural forms known as
PROTEIN STRUCTURE – types and function Read More »
Biotechnology, Molecular Microbiology
Purines are heterocyclic aromatic organic compound that consist of a pyrimidine ring fused to an imidazole ring. Purines are the larger of the two types of bases found in DNA. Adenine (A) and guanine (G) are purines. Adenine is always paired with thymine, and guanine is always paired with cytosine. Purines unlike pyrimidines (which have
PURINES & PYRIMIDINES Read More »
Biotechnology, Molecular Microbiology
Nucleotides are nucleosides with one or more phosphate groups covalently attached to the 3′ or 5′-hydroxyl group(s) (OH–) of a pentose sugar. A nucleoside is one of the four (4) DNA bases (i.e. adenine, guanine, cytosine and thymine) covalently attached to the carbon-one (C1) position of a sugar molecule such as the pentose sugar. Deoxyribose
Microbial cells employ a variety of mechanisms to uptake nutrients (including macromolecules, inorganic ions, water and other small molecules) from their natural environment or from artificially prepared cultured media which are precisely designed to provide all the essential nutritional requirements and growth factors necessary for microbial or bacterial growth. The cell wall or outer covering
Mechanisms for uptake of nutrients by microorganisms – diffusion & active transport Read More »
Microbial Physiology & Metabolism, General Microbiology
Living organisms vary in terms of their mode of nutrition i.e. how they feed or obtain their food. Some organisms are known as autotrophs because they can manufacture their own food; and examples include green plants and green algae. Autotrophs use carbondioxide (CO2) as their sole source of carbon for growth. Plants contain chlorophyll which
NUTRITIONAL GROUPS OF MICROORGANISMS Read More »
General Microbiology, Microbial Physiology & Metabolism
Bacterial Nutritionis importantfor the optimum growth of the organism because it is the only means by which the organism can acquire all necessary materials required for its cellular biosynthetic activities as well as for the generation of energy (i.e. adenosine triphosphate, ATP). Nutrients are substances required for energy production and other biosynthetic activity necessary for
Microbial (Bacterial) Nutrition Read More »
Microbial Physiology & Metabolism, General Microbiology
Corynebacterium diphtheriae is a Gram-positive, non-spore forming, aerobic, rod-shaped and motile bacterium that causes diphtheria, an upper respiratory tract illness. They are pleomorphic organisms exhibiting different characteristic morphological shapes including V-shapes, irregular shapes and club-shapes.C. diphtheriae and other species in the genera Corynebacteria grow on the mucous membrane of the upper respiratory tract, skin, nares
CORYNEBACTERIUM DIPHTHERIAE Read More »
Bacteriology
Vibrio cholerae is a Gram-negative, oxidase positive, spiral, non-spore forming, facultative, motile, curved or straight rod bacterium that causes severe diarrheal disease known as cholera in humans. Cholera, which is one of the leading causes of waterborne infections in developing countries, is a profuse watery diarrheal disease that is associated with extreme dehydration following excessive
Neisseria gonorrhoeae is a Gram-negative, oxidase-positive, non-motile, non-sporulating, non-capsulate, diplococcus found asymptomatically in humans. N. gonorrhoeae is found in the family Neisseriaceae and genus Neisseria which contains two important human pathogens viz: N. gonorrhoeae and N. meningitidis (which causes meningococcal meningitis, an inflammation of the meninges of the brain and spinal cord). Though the syndromes
NEISSERIA GONORRHOEAE Read More »
Bacteriology