PRESUMPTIVE TEST The presumptive test provides a preliminary estimate of bacterial density present in a test sample based on enrichment in minimally restrictive tube (broth) culture media. It is the first step of the MPN procedure for feacal coliform testing carried out on public health samples including water, milk and food. The original test sample […]
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Environmental & Soil Microbiology
The estimation of the number of microorganisms including bacteria and fungi present in public health sample including water, food, beverage, or other products is one of the major tasks of microbiologists especially those working in water treatment plants, food industries and in other government public health establishments. After isolation and estimating the number of microorganisms
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Environmental & Soil Microbiology
The genotypic detection and characterization of antibiotic resistant genes in pathogenic bacteria is more specific in characterizing resistance genes than the phenotypic detection methods. The term genotypic is derived from genotype – which is the complete genetic makeup of an organism. Genotype describes the overall composition of the genetic information found in an organism. Thus,
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Antimicrobial Susceptibility Testing (AST) & Antibiogram, Pharmaceutical Microbiology, Techniques in Microbiology Lab
Helping the physician select the best treatment at a much faster pace based on the right microbial identification and antimicrobial susceptibility test is crucial in any infectious disease management and patient total wellbeing. Clinical microbiology laboratories are the first lines of defense for the detection of antibiotic resistance from clinical pathogens and/or samples. And the
Sulphonamides or sulpha drugs are generally known as folate synthesis inhibitors because they inhibit the synthesis of folic acid, an important precursor for the synthesis of nucleic acids in pathogenic bacteria. They are antimetabolites; and antibiotics in this category include pyrimethamine, trimethoprim, sulphamethoxazole and sulphamethoxazole-trimethoprim. Sulphonamides are the largest antibiotic family that acts as
Tetracyclines are general purpose antibiotics used for a variety of clinical applications, and they include tetracycline, chlortetracycline, oxytetracycline, dimethyl chlortetracycline, minocycline and doxycycline. Antibiotics in this category are protein synthesis inhibitors like the macrolides, but tetracyclines bind to the 30S ribosomal subunit of bacterial ribosomes during protein synthesis. They are used to treat a wide
Bacteria have evolved to survive in diverse environments. They survive exposure to harsh chemicals including antibiotics, and they also survive difficult growth conditions. They have learned to “detoxify” harmful substances e.g. antibiotics. Antibiotic resistance can either be intrinsic or acquired. INTRINSIC (INNATE) RESISTANCE Some bacteria are said to possess innate/intrinsic resistance against antibacterial action put
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Antibiotic Resistance / Antimicrobial Resistance (AMR), Antimicrobial Agents & Antibiotics, Antimicrobial Susceptibility Testing (AST) & Antibiogram, Pharmaceutical Microbiology
Antimicrobial agents, particularly antibiotics are the most significant class of pharmaceuticals and are one of the most influential medical inventions of the twentieth century. They have undeniably been a boon to human society in the fight against bacteria, saving millions of lives. Nonetheless, the number of infections caused by multidrug-resistant (MDR) bacteria is increasing across
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Antibiotic Resistance / Antimicrobial Resistance (AMR), Antimicrobial Agents & Antibiotics, Antimicrobial Susceptibility Testing (AST) & Antibiogram, Pharmaceutical Microbiology
PCR is the acronym for “polymerase chain reaction”. Polymerase chain reaction is the molecular biology technique that is used to amplify or copy specific gene sequences or nucleotides of a DNA molecule or gene. It was invented by Kary Mullis and his colleagues in the early 1980s; and PCR technique is the most widely used
Restriction endonucleases are DNA cutting enzymes specifically found and isolated from bacteria; and which nick specific sites on a nucleotide sequence known as restriction sites. Restriction sites are the different sites on a DNA molecule that is nicked by a particular restriction enzyme. Several types of restriction enzymes exist, and they are primarily sourced from
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Biotechnology, Molecular Microbiology, Techniques in Microbiology Lab