Gram staining: principle, procedure and results february 2, 2015 tankeshwar bacteriology , staining techniques in microbiology 47 gram staining method, the most important procedure in microbiology, was developed by danish physician hans christian gram in 1884. A special stain called the acid-fast stain may be done in the laboratory to identify the tuberculous bacilli different types of microorganisms may be identified using gram stain a fungal culture may be done if a fungal infection is suspected and a viral culture is done to detect viral infection such as pneumonia. 7 gram stain and koh test introduction gram stain procedure is the most used staining procedure in pathology labs it is fast, inexpensive and informative however, to exclude the possibility of. The main purpose of capsule stain is to distinguish capsular material from the bacterial cell a capsule is a gelatinous outer layer secreted by bacterial cell and that surrounds and adheres to the cell wall most capsules are composed of polysaccharides, but some are composed of polypeptides.
Identification completed after lab on thursday may 14th out of a possible 70 points you (verify with instructor) o morphology & arrangement • capsule stain • spore stain (only if gram-negative) • acid fast stain (only if gram-negative rod) • motility (via wet mount) staphylococcus aureus staphylococcus epidermidis streptococcus. Staphylococcus aureus & salmonella typimurium used to distinguish bacterial types gram stain, acid-fast stain two diseases caused by acid-fast bacteria and the species related: tb: mycobacterium tuberculosis microbio 225 (lab test 3) selective and differential media, imvic, biochem tests (with some bacterial samples). Best answer: 1 staphylococci do not produce endospores 2 s epidermidis does not produce a capsule, and 3 staphylococci are not acid fast in other words all of these tests should be negative for staphylococci.
Lab practical one report unknown bacteria staining gram acid fast spore the first practical for microbiology was staining of an unknown bacteria professor goode provided an unlabeled bacteria in which each individual were to conduct gram, acid fast , and spore staining tests from memory. Negative report in 5 days ideally, blood cultures should be drawn before the first dose of antibiotics, but antibiotics should not be withheld because of a delay in getting blood drawn. Stab one with pseudomonas aeruginosa and the other with staphylococcus aureus stab the bacterium about 1/2 - 3/4 of an inch into the agar, taking care not to tilt or twist the loop so that the loop comes up through the same cut as it went down. 27 lab 3 results i differential stains a gram stain draw and label examples of escherichia coli and staphylococcus epidermidis b acid-fast stain draw and label examples of mycobacterium smegmatis and staphylococcus epidermidis mycobacterium smegmatis & staphylococcus epidermidis questions: 1 what is the difference between a simple and a differential stain_____. Example lab report of staphylococcus aureus s aureus is a gram positive bacterium that when looked at under a microscope it appears to be a cluster of what after doing a gram stain on the bacterium, it was determined that this bacterium was a gram negative this is used to find out if a bacterium can produce acid that ferments glucose.
Gram-indeterminate bacteria are best stained using acid-fast staining techniques examples include many species of mycobacterium, including m tuberculosis and m leprae the gram stain is a very important preliminary step in the initial characterization and classification of bacteria. Staphylococcus aureus: gram(+) cocci in pairs or clusters name-derivation: grape-like, yellow-gold stain: acid-fast smear is done on the suspension from the prepared specimen above lab will report a b-subtype as it is associated with prognosis. Staphylococcus aureus is a gram-positive, round-shaped bacterium that is a member of the firmicutes, and it is a member of the normal flora of the body, frequently found in the nose, respiratory tract, and on the skin. 32 microscopic techniques: dyes and staining 47 figure 314 gram stain (a) steps in the gram stain procedure (b) results of a gram stainthe gram-positive cells (purple) are staphylococcus aureus the gram-negative cells (reddish-pink) are escherichia coli. Acid-fast vs non acid-fast – acid-fast: bacteria which retain the primary stain carbolfuschsin in their cell walls (even if treated with a strong decolorizing agent, acid alcohol) non acid-fast: bacteria that do not retain the initial stain of carbolfuschsin, and are decolorized by acid alcohol and take up the counterstain methylene blue.
In the following exercise, you will prepare an acid-fast stain of mixture of mycobacterium smegmatis and staphylococcus aureus using the kinyoun method for acid-fast staining m smegmatis is a nonpathogenic, acid-fast rod that occurs in soil and on the external gentalia of humans. A gram stain of mixed staphylococcus aureus (staphylococcus aureus atcc 25923, gram-positive cocci, in purple) andescherichia coli (escherichia coli atcc 11775, gram-negative bacilli, in red), the most common gram stain reference bacteria gram staining (or gram’s method) is a method of differentiating bacterial species into two large groups. Acid-fast stain- principle, procedure, interpretation and examples june 12, 2018 may 8, 2015 by sagar aryal it is the differential staining techniques which was first developed by ziehl and later on modified by neelsen. After all tests had been successfully conducted, unknown gram + bacteria (a) had been determined to be staphylococcus epidermidis gram staining bacteria (a) allowed for the elimination of all gram – bacteria, and all rod shaped cells. Study flashcards on microbiology: lab exercise 5-gram staining at cramcom quickly memorize the terms, phrases and much more cramcom makes it easy to get the grade you want.
Simple vs differential stain methylene blue basic fuchsin crystal violet differential staining gram staining acid-fast technique spore staining staphylococcus aureus unidentified bacterium bacillus subtilis differentiates between two groups, gram positive and gram negative. Learn lab quiz 8 acid fast stain with free interactive flashcards choose from 500 different sets of lab quiz 8 acid fast stain flashcards on quizlet. Unknown lab report unknown number 108 caroline coley microbiology fall/2013 introduction microorganisms exist everywhere in nature bacteria, viruses and fungi have been a leading cause of death in the history of mankind.
After a successful gram stain it was classified as a gram positive cocci which narrowed it down to three bacteria staphylococcus aureus, staphylococcus epidermidis, and enterococcus faecalis since s aureus was isolated onto an msa plate and broth that turned yellow, which indicates a positive for acid, it took staphylococcus epidermidis off. After staining with basic fuchsin, acid-fast bacteria resist decolonization by acid-alcohol non-acid-fast bacteria are counterstained with methylene blue used to distinguish acid-fast bacteria such as m tuberculosis , from non-acid-fast cells. Staining and 3) will retain the original cell morphology after fixation and staining after you have stained your bacterial smears, you will examine them with the oil immersion lens, noting the morphological and staining characteristics of each species.