There are a variety of staining methods like simple, differential and special staining that are used in labs to examine the bacteria. Module morphology and classification of bacteria microbiology 10 notes stains. General microbiology morphology of bacterial cell, staining procedures for bacteria, culture media for bacteria, cultivation and isolation techniques for bacteria, preparation of pure cultures. Hematoxylin has a deep bluepurple color and stains nucleic acids by a complex, incompletely understood reaction. Different types of staining methods are used to make the cells and their internal. Methods of culturing microorganisms 3 five basic techniques 4 fig. The most commonly used instrument in the microbiology laboratory for the sterilization of media and glassware is the autoclave. Gram staining is a differential staining technique that differentiates bacteria into two groups. Staining techniques in some cases, staining is unnecessary, for example when microorganisms are very large or when motility is to be studied, and a drop of the microorganisms can be placed directly on the slide and observed. Staining tray, wash bottles, inoculation loop microscopic glass slides, bunsen burner, blotting papers, microscopes. Staining techniques in microbiology linkedin slideshare.
Staining is a technique used to enhance contrast in samples, generally at the microscopic level. Stains and dyes are frequently used in histology the study of tissue under the microscope and in the medical fields of histopathology, hematology, and cytopathology that focus on the study and diagnoses disease at a microscopic level. These are of two types, namely direct and indirect staining. The application of molecular technology in medicine is almost endless, some of the applications of. Stains may be used to define biological tissues highlighting. The most widely used staining procedure in microbiology is the gram stain, discovered by the danish scientist and physician hans christian joachim gram in 1884. Types of different staining techniques of microorganisms. Gram stain protocols american society of microbiology. Basic microbiology notes online microbiology notes. Gram staining primary stain step 1 crystal violet is the primary stain used in the gram staining process it is not specific for gram positive cells and it stains everything the same color purple. The steps of the gram stain procedure are listed below and illustrated in table 1. Basic techniques in biochemistry, microbiology and molecular biology pp 111116 cite as.
This technique differentiates species of mycobacterium from other bacteria. The word gram is always spelled with a capital, referring to hans christian gram, the inventor of gram staining gram staining principles gram staining is used to determine gram status to classify bacteria broadly. S ome staining techniques, such as the gram and ziel neelsen stains, although of great diagnostic value because of their differential staining properties for specific bacteria, reveal li ttle. Other differential staining methods include the endospore stain to identify endosporeforming bacteria, the acidfast stain to discriminate mycobacterium species. The acidfast microorganisms retain the pinkred color because carbofuschsin is more soluble in the cell wall lipids than in acidalcohol. Cover different classification schemes for grouping bacteria, especially the use of the gram stain 2. Staining is a supplementary method that gives divergence to the microscopic image for better vision under the microscope. Heatfixed bacterial smears refer staining techniques in microbiology 1st edition by dr. This list may not reflect recent changes learn more. Microscopy using the microscope 22 stained preparations 23 making a smear 23 a simple stain 24 a differential stain. Cell staining in microscopy types, techniques, preparations.
Different types of staining methods are used to make the cells and. Some staining techniques, such as the gram and ziel neelsen stains, although. Staining techniques in microbiology a presentation by g. Sep 25, 2019 stains may be used to define and examine different types of microbes, various stages of cellular life e. Medical laboratory sciences medical bacteriology mls. Different types of staining methods are used to make the cells and their internal structures more visible under the light microscope. Instruments used in microbiology lab with principle and uses. Chemically the cell wall is composed of peptidoglycan.
This staining technique divides bacteria into two groups namely acidfast and non acidfast. Introduction as bacteria consist of clear protoplasmic matter, differing but slightly in refractive index from the medium in which they are growing, it is difficult with the ordinary microscope, except when special methods of illumination are used, to set them in the unstained condition. Then the cells are washed with a dilute acidalcohol solution. Histologic staining options available include, but are not limited to. It determines the cell shape, size and arrangement of the microorganism. This manual has been written for a righthanded person. Invivo staining is the process of dyeing living tissue in vivo means in life as contrasted to invitro staining. Staining of bacterial cells objective to learn the techniques of smear preparation, gram staining, nigrosin staining and correlating the results of gram staining with koh test. Mycobacterium and many nocardia species are called acidfast because. By exploiting this phenomenon, an alternative gram staining technique has been developed. To learn the techniques of gram staining, nigrosin staining and koh test. Staining, therefore, is of primary importance for the. Another differential stain technique is the acidfast technique. Blood is composed of the blood cells which accounts for 45% of the blood tissue by volume, with the remaining 55% of the volume composed of plasma, the liquid.
Basic microbiologymlsbmic224 staining methods l 16, 17. Feb 03, 2015 staining techniques in microbiology 1. Stains may be used to define and examine different types of microbes, various stages of cellular life e. Bhanu prakash usmle, fmge and neet pg 14,870 views. The previous lab introduced simple staining techniques that enable. Microscopic slides endospores a stained preparation of bacillus subtilis showing endospores as uncoloured and the vegetative cell as. Biochemical tests the sole purpose of biochemical test in microbiology is to differentiate between various classes of bacteria by studying their enzymatic activities. Several different types of staining procedure are known today which. Staining methods simple staining, negative staining, grams. Fluorescencelabeled wheat germ agglutinin binds specifically to nacetylglucosamine in the outer peptidoglycan layer of grampositive bacteria. Stain or dye is the synthetic chemical which is derived from nitrobenzene or aniline. Coloring microorganisms with a dye that emphasizes certain structures.
Then apart from all this some other staining techniques are there for identification of fungus like lactophenol cotton blue staining, and many other techniques. In microbiology, differential staining techniques are used more often than simple stains as a means of gathering information about bacteria. Microscopy refers to the practice that involves the use of a microscope for the purposes of observing small scale structures that cannot be viewed using the naked eye and often cell staining is necessary as s tructures are difficult to discern due to insufficient contrast. Bacterial classification, structure and function introduction the purpose of this lecture is to introduce you to terminology used in microbiology. The instruments used in the microbiology labs include a bunch of different kinds of instruments required for a lot of different processes conducted within those laboratories. Stains are salts composed of a positive ion cation and a negative ion anion. Microbiological laboratory techniques clinical gate.
Composition, types and mechanism of staining composition. Testing sensitivity to antimicrobial substances 21 2. Blood cells are the cells which are produced during hematopoiesis and found mainly in the blood. Introduction observation of bacteria with conventional bright field microscopy yields relatively little useful information. Negatively charged acid radicals imparts color in eosin, acid fuchsine, malachite green, nigrosin. The peptidoglycan layer of gramnegative bacteria is covered by a membrane and is not labeled by the lectin. In the laboratory, viruses have served as useful tools to better understand cellular mechanisms. It is a technique that is widely used for the examination of cells, tissues and cellular components. Gram staining is the common, important, and most used differential staining techniques in microbiology, which was introduced by danish bacteriologist hans christian gram in 1884. Uk standards for microbiology investigations issued by the standards unit, public health england. This staining technique is used to demonstrate the presence of acid fast bacilli. Some staining techniques, such as the gram and ziel neelsen stains, although of great diagnostic value because of their differential staining properties for specific bacteria, reveal little. Sep 19, 2016 gram staining procedure animation microbiology principle, procedure, interpretation duration.
The most common type of acid fast bacteria is mycobacteria. Types of staining techniques used in microbiology and their. It is one of the most important and widely used differential staining techniques in microbiology. Make a thin film of the material on a clean glass slide, using a sterile loop or swab for viscous specimens. The following 61 pages are in this category, out of 61 total. Microbiology module common staining technique microbiology 22 notes 2. Heat or a lipid solvent is used to carry the first stain, carbolfuchsin, into the cells. Make a thin film of the material on a clean glass slide, using a. Some staining techniques involve the application of only one dye to the. This technique was introduced in 1884 by danish physician christian gram. Objectives to learn the technique of smear preparation.
There are two types pili namely nonsex pili common pili eg. Staining microscopic specimens microbiology lumen learning. It may be demonstrated by microdissection, reaction with specific antibodies, mechanical rupture of the cell, differential staining procedures or by electron microscopy. This test differentiate the bacteria into gram positive and gram negative bacteria, which helps in the classification and differentiations of microorganisms. Mycobacterium species resist the effect of the acid. Microbiology module common staining technique microbiology 24 notes indeterminate groups as well.
Gram staining helps to identify bacterial pathogens in specimens and cultures by their gram reaction gram positive and gram negative and morphology coccirod. The purpose of this lesson is to provide a general overview of laboratory techniques used in the. Wikimedia commons has media related to microbiology techniques. Staining tray, wash bottles, inoculation loop microscopic glass. Molecular techniques in clinical microbiology molecular biology is the science of biomolecules. To perform this staining, it requires the use of a single stain only. Differential staining methods, which typically require more than one stain and several steps, are referred to as such because they permit the differentiation of cell types or cell structures.
Introduction to microbiology culture techniques youtube. Hematoxylin and eosin staining technique functions to recognize different types of tissues and their morphological changes, especially in cancer diagnosis. The extremely minute size of this wonderful structure remained an obstacle for. Gram stain the previous lab introduced simple staining techniques that enable microbiologists to observe the morphological characteristics of bacteria. Already available was a staining method designed by robert. Cell staining in microscopy types, techniques, preparations and procedures. Acknowledgments uk standards for microbiology investigations uk smis are developed under the auspices of public health england phe working in partnership with the national.
Gram staining procedure animation microbiology principle, procedure, interpretation duration. To use and relate the gram stain to the study of bacterial cell morphology, and as an. Different types of microscopes cell is the basic unit of life. A detailed discussion of the different types of physical and chemical methods of sterilization is provided in chapter 19 physical and chemical methods of control. Methylene blue, polychrome blue or carbol fuchsin to act as simple stain. Virology techniques introduction virology is a field within microbiology that encompasses the study of viruses and the diseases they cause. Even though the term biomolecules includes all molecules such as proteins, fatty acids etc, it is refers to nucleic acid these days. Bacteria have nearly the same refractive index as water, therefore, when they. Alternate gram staining technique using a fluorescent lectin. Gram stain is a very important differential staining techniques used in the initial characterization and classification of bacteria in microbiology. It was developed by danish microbiologist hans christian gram in 1884 as an effective method to distinguish between bacteria with different types of cell walls, and even today it remains one of the most frequently used staining techniques.
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