This document provides an overview of biochemical methods used for bacterial identification. It discusses why bacterial identification is important, the typical identification scheme involving isolation, staining, culturing, and biochemical/molecular tests. Several common biochemical tests are described in detail, including their principles, media used, and how to interpret results. These tests analyze bacterial metabolism of carbohydrates, proteins, lipids and other compounds. Automated identification systems that can rapidly identify bacteria based on biochemical profiles are also mentioned.
Microbiology of E coli giving basic of Escherichia coli, its morphology, cultural and biochemical characteristics, Antigenic character, pathogenesis, laboratory diagnosis, prevention and control
Oxidase Test Microbiology - Principle, Procedure, Limitations, Results, QC - in lab #Oxidase Test
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Qualification
Maneesha M Joseph
MSc MLT (Microbiology)
Assistant Professor
Baby memorial college of allied Health science
Kozhikode
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Microbiology of E coli giving basic of Escherichia coli, its morphology, cultural and biochemical characteristics, Antigenic character, pathogenesis, laboratory diagnosis, prevention and control
Oxidase Test Microbiology - Principle, Procedure, Limitations, Results, QC - in lab #Oxidase Test
As the channel name suggests, our channel will be a perfect lounge for the malayali medicos..we wil be covering videos which will be like lecture classes related to the subjects biochemistry and microbiology in which we are specialised.. It will be a better learning experience for the students especially for those who are not able to understand and follow the normal classes in college..we assure the students that you will get a basic idea regarding the topic and extra reading can be done from the reference textbooks...
If you like my video
#like
#comment
#subscribe my channel
don't forget to subscribe my channel
Qualification
Maneesha M Joseph
MSc MLT (Microbiology)
Assistant Professor
Baby memorial college of allied Health science
Kozhikode
Our Partner Channel
Health & Voyage channel link - https://youtu.be/nzKqRVjlwc0
#Oxidase Test
#Medical
#Microbiology
# malayalam lecturer
#Mallu Medicos Lounge
#MalluMedicosLounge
#MLT
The above presentation provides information regarding the biochemical tests in microbiology. And the core chemical reactions happens during these tests are been explained. The chemical reactions involved in the biochemical tests are been explained with reactions.
Cancer cell metabolism: special Reference to Lactate PathwayAADYARAJPANDEY1
Normal Cell Metabolism:
Cellular respiration describes the series of steps that cells use to break down sugar and other chemicals to get the energy we need to function.
Energy is stored in the bonds of glucose and when glucose is broken down, much of that energy is released.
Cell utilize energy in the form of ATP.
The first step of respiration is called glycolysis. In a series of steps, glycolysis breaks glucose into two smaller molecules - a chemical called pyruvate. A small amount of ATP is formed during this process.
Most healthy cells continue the breakdown in a second process, called the Kreb's cycle. The Kreb's cycle allows cells to “burn” the pyruvates made in glycolysis to get more ATP.
The last step in the breakdown of glucose is called oxidative phosphorylation (Ox-Phos).
It takes place in specialized cell structures called mitochondria. This process produces a large amount of ATP. Importantly, cells need oxygen to complete oxidative phosphorylation.
If a cell completes only glycolysis, only 2 molecules of ATP are made per glucose. However, if the cell completes the entire respiration process (glycolysis - Kreb's - oxidative phosphorylation), about 36 molecules of ATP are created, giving it much more energy to use.
IN CANCER CELL:
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
introduction to WARBERG PHENOMENA:
WARBURG EFFECT Usually, cancer cells are highly glycolytic (glucose addiction) and take up more glucose than do normal cells from outside.
Otto Heinrich Warburg (; 8 October 1883 – 1 August 1970) In 1931 was awarded the Nobel Prize in Physiology for his "discovery of the nature and mode of action of the respiratory enzyme.
WARNBURG EFFECT : cancer cells under aerobic (well-oxygenated) conditions to metabolize glucose to lactate (aerobic glycolysis) is known as the Warburg effect. Warburg made the observation that tumor slices consume glucose and secrete lactate at a higher rate than normal tissues.
Professional air quality monitoring systems provide immediate, on-site data for analysis, compliance, and decision-making.
Monitor common gases, weather parameters, particulates.
Richard's aventures in two entangled wonderlandsRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
THE IMPORTANCE OF MARTIAN ATMOSPHERE SAMPLE RETURN.Sérgio Sacani
The return of a sample of near-surface atmosphere from Mars would facilitate answers to several first-order science questions surrounding the formation and evolution of the planet. One of the important aspects of terrestrial planet formation in general is the role that primary atmospheres played in influencing the chemistry and structure of the planets and their antecedents. Studies of the martian atmosphere can be used to investigate the role of a primary atmosphere in its history. Atmosphere samples would also inform our understanding of the near-surface chemistry of the planet, and ultimately the prospects for life. High-precision isotopic analyses of constituent gases are needed to address these questions, requiring that the analyses are made on returned samples rather than in situ.
Multi-source connectivity as the driver of solar wind variability in the heli...Sérgio Sacani
The ambient solar wind that flls the heliosphere originates from multiple
sources in the solar corona and is highly structured. It is often described
as high-speed, relatively homogeneous, plasma streams from coronal
holes and slow-speed, highly variable, streams whose source regions are
under debate. A key goal of ESA/NASA’s Solar Orbiter mission is to identify
solar wind sources and understand what drives the complexity seen in the
heliosphere. By combining magnetic feld modelling and spectroscopic
techniques with high-resolution observations and measurements, we show
that the solar wind variability detected in situ by Solar Orbiter in March
2022 is driven by spatio-temporal changes in the magnetic connectivity to
multiple sources in the solar atmosphere. The magnetic feld footpoints
connected to the spacecraft moved from the boundaries of a coronal hole
to one active region (12961) and then across to another region (12957). This
is refected in the in situ measurements, which show the transition from fast
to highly Alfvénic then to slow solar wind that is disrupted by the arrival of
a coronal mass ejection. Our results describe solar wind variability at 0.5 au
but are applicable to near-Earth observatories.
Observation of Io’s Resurfacing via Plume Deposition Using Ground-based Adapt...Sérgio Sacani
Since volcanic activity was first discovered on Io from Voyager images in 1979, changes
on Io’s surface have been monitored from both spacecraft and ground-based telescopes.
Here, we present the highest spatial resolution images of Io ever obtained from a groundbased telescope. These images, acquired by the SHARK-VIS instrument on the Large
Binocular Telescope, show evidence of a major resurfacing event on Io’s trailing hemisphere. When compared to the most recent spacecraft images, the SHARK-VIS images
show that a plume deposit from a powerful eruption at Pillan Patera has covered part
of the long-lived Pele plume deposit. Although this type of resurfacing event may be common on Io, few have been detected due to the rarity of spacecraft visits and the previously low spatial resolution available from Earth-based telescopes. The SHARK-VIS instrument ushers in a new era of high resolution imaging of Io’s surface using adaptive
optics at visible wavelengths.
A brief information about the SCOP protein database used in bioinformatics.
The Structural Classification of Proteins (SCOP) database is a comprehensive and authoritative resource for the structural and evolutionary relationships of proteins. It provides a detailed and curated classification of protein structures, grouping them into families, superfamilies, and folds based on their structural and sequence similarities.
Slide 1: Title Slide
Extrachromosomal Inheritance
Slide 2: Introduction to Extrachromosomal Inheritance
Definition: Extrachromosomal inheritance refers to the transmission of genetic material that is not found within the nucleus.
Key Components: Involves genes located in mitochondria, chloroplasts, and plasmids.
Slide 3: Mitochondrial Inheritance
Mitochondria: Organelles responsible for energy production.
Mitochondrial DNA (mtDNA): Circular DNA molecule found in mitochondria.
Inheritance Pattern: Maternally inherited, meaning it is passed from mothers to all their offspring.
Diseases: Examples include Leber’s hereditary optic neuropathy (LHON) and mitochondrial myopathy.
Slide 4: Chloroplast Inheritance
Chloroplasts: Organelles responsible for photosynthesis in plants.
Chloroplast DNA (cpDNA): Circular DNA molecule found in chloroplasts.
Inheritance Pattern: Often maternally inherited in most plants, but can vary in some species.
Examples: Variegation in plants, where leaf color patterns are determined by chloroplast DNA.
Slide 5: Plasmid Inheritance
Plasmids: Small, circular DNA molecules found in bacteria and some eukaryotes.
Features: Can carry antibiotic resistance genes and can be transferred between cells through processes like conjugation.
Significance: Important in biotechnology for gene cloning and genetic engineering.
Slide 6: Mechanisms of Extrachromosomal Inheritance
Non-Mendelian Patterns: Do not follow Mendel’s laws of inheritance.
Cytoplasmic Segregation: During cell division, organelles like mitochondria and chloroplasts are randomly distributed to daughter cells.
Heteroplasmy: Presence of more than one type of organellar genome within a cell, leading to variation in expression.
Slide 7: Examples of Extrachromosomal Inheritance
Four O’clock Plant (Mirabilis jalapa): Shows variegated leaves due to different cpDNA in leaf cells.
Petite Mutants in Yeast: Result from mutations in mitochondrial DNA affecting respiration.
Slide 8: Importance of Extrachromosomal Inheritance
Evolution: Provides insight into the evolution of eukaryotic cells.
Medicine: Understanding mitochondrial inheritance helps in diagnosing and treating mitochondrial diseases.
Agriculture: Chloroplast inheritance can be used in plant breeding and genetic modification.
Slide 9: Recent Research and Advances
Gene Editing: Techniques like CRISPR-Cas9 are being used to edit mitochondrial and chloroplast DNA.
Therapies: Development of mitochondrial replacement therapy (MRT) for preventing mitochondrial diseases.
Slide 10: Conclusion
Summary: Extrachromosomal inheritance involves the transmission of genetic material outside the nucleus and plays a crucial role in genetics, medicine, and biotechnology.
Future Directions: Continued research and technological advancements hold promise for new treatments and applications.
Slide 11: Questions and Discussion
Invite Audience: Open the floor for any questions or further discussion on the topic.
1. SAKEENA ASMI T
MAHATMA GANDHI UNIVERSITY
BIOCHEMICAL METHODS
FOR IDENTIFICATION OF
BACTERIA
2. • To distinguish harmless microbes from
pathogenic microbes.
• Characterize an outbreak of disease and
determine the source.
• Verify the authenticity of pathogenic strain
for quality control purposes.
• Determine appropriate antimicrobial therapy.
• Basically for the prevention, control and
treatment of a disease.
WHY IS IDENTIFICATION IMPORTANT?
4. Biochemical tests are the tests used for
identification of bacteria species based on the
differences in the biochemical activities of
different bacteria.
Differences in carbohydrate metabolism,
protein metabolism, fat metabolism, production
of certain enzymes, ability to utilize a particular
compound etc.
Each species of bacteria have a well defined set
of metabolic activities different from all other
species
These biochemical fingerprints are properties
controlled by the bacterial enzymes.
WHAT ARE BIOCHEMICAL TESTS?
5. 1. Indole test
2. Methyl red test
3. Voges-Proskauer test
4. Citrate utilisation test
5. Carbohydrate fermentation test
6. Triple sugar iron(TSI)test
7. Nitrate reduction test
8. Urease test
9. Oxidase test
10. Catalase test
11. Oxidation-fermentation(O/F)test
12. O-Nitrophenyl galactosidase(ONPG)test
IMViC test
Intracellular
Enzyme
Activity
6. 1. Coagulase test
2. Gelatinase test
3. Starch hydrolysis test
4. Lipid hydrolysis test
5. Deoxyribonuclease test(DNase
test)
Extracellular
Enzyme
Activity
7. INDOLE TEST
To determine the ability of microbe to degrade the amino acid tryptophan.
MEDIA : Tryptophan 1% or peptone broth
REAGENT : Kovacs’ reagent (Dimethylamine benzaldehyde)
PRINCIPLE:
Tryptophanase
Tryptophan Indole + pyruvic acid + ammonia
Indole + Kovacs reagent Rosindole + H2O
(Cherry red colour
compound)
Hcl
Butanol
POSITIVE : Cherry red coloured ring at the
interface of reagent and broth.
Eg: E.coli
NEGATIVE : No colour change is observed.
Eg: Klebsiella
8. SPOT INDOLE
To perform this test, a test colony is smeared in a
piece of filter paper saturated with Kovac’s
reagent. The appearance of red colour indicates a
positive test.
9. METHYL RED TEST (MR TEST)
To determine the ability of microbes to oxidize glucose with production
and stabilization of high content of acid end products.
MEDIA : MR broth – peptone, glucose, dipotassium phosphate &
distilled water.
REAGENT : MR reagent – MR 0.1g in 300ml of 95% ethanol & DW 200ml.
PRINCIPLE:
Glucose Mixed acids (pH less than 4.4) + Methyl red
Red colour
POSITIVE : Red colour is observed. Eg: E.coli
NEGATIVE : Yellow colour is observed.
Eg: Klebsiella
10. VOGES-PROSKAUER TEST (VP TEST)
To determine the ability of microbes to produce non acidic or neutral end
products.
MEDIA : VP broth ( same as MR broth)
REAGENT : Barrits A – Alpha naphthol 5%
Barrits B – 40% Potassium hydroxide
PRINCIPLE :
Glucose Pyruvate Acetoin 2, 3-butanediol
Acetoin + α-napthol (0.6ml) Diacetyl
(Pink coloured complex)
40% KOH (0.2ml)
POSITIVE : Pink colour is observed.
Eg: Klebsiella
NEGATIVE : No colour change is observed.
Eg: E.coli
11. CITRATE UTILISATION TEST
To determine the ability of the microbes to ferment citrate as sole carbon
source.
MEDIA : Simmons citrate medium
INDICATOR : Bromothymol blue
PRINCIPLE:
Sodium citrate Pyruvic acid + Oxaloacetic acid+ CO2
Excess sodium from + CO2 + H2O Na2CO3 (pH ) (green blue)
sodium citrate
Citrate permease
POSITIVE : Change of colour from green to blue
Eg: Klebsiella
NEGATIVE : No colour change is observed.
Eg: E.coli
12. CARBOHYDRATE FERMENTATION TEST
To determine the ability of microbes to ferment specific carbohydrates with the
production of acid and/or gas.
MEDIA : Nutrient broth with sugars (Glucose, lactose, sucrose, maltose)
INDICATOR : Phenol red or Bromocresol purple to detect acid & Durham's tube to
detect gas.
PRINCIPLE :
Carbohydrate Organic acids + CO2 + H2
Acid lowers the pH which can be detected by pH indicators.
Gas production (CO2) can be detected in Durham’s tube.
POSITIVE : Acid only – colour change to yellow (A)
Eg: S.aureus
Acid & Gas – colour change to yellow
& bubble in durham's tube(A/G)
Eg: E.coli, Klebsiella
NEGATIVE : No colour change is observed.
Eg: Pseudomonas
fermentation
13. TRIPLE SUGAR IRON TEST (TSI TEST)
To differentiate among and between the members of Enterobacteraceae and
screen for enteric pathogens based on carbohydrate fermentation and H2S
production.
MEDIA : TSI agar - glucose 0.1%, lactose & sucrose 1% concentration, protein
source(peptone), NaCl, Sodium thiosulfate, Ferric ammonium citrate.
INDICATOR : Phenol red (pH indicator)
PRINCIPLE :
Carbohydrates Acid + CO2
Peptones NH3 (makes medium alkaline)
Phenol red
Acid lowers the pH and ammonia increases the pH which can be detected by
pH indicators.
Gas production (CO2) can be detected by cracks in the medium.
Yellow
Red
acid
alkali
14. Bacteria + Sodium thiosulfate H2S gas
H2S gas + Fe3+ FeS (black precipitate)
H2S can be detected by black precipitate formation in the medium.
acid environment
15. Result interpretation:
• Red slant, red butt, no gas, no H2S - K/K no H2S
• Red slant, yellow butt, no gas, no H2S - K/A no H2S
• Yellow slant, yellow butt, gas, no H2s - A/ A no H2S
• Yellow slant, yellow butt, gas, H2s - A/ A H2S
• Red slant, yellow butt, gas, H2S - K/ A H2S
Alkaline slant /acidic butt only glucose is fermented
Acidic slant / acidic butt glucose, sucrose, lactose all 3 sugars
are fermented
Bubbles or cracks present gas production
Black precipitate present H2S production
16. NITRATE REDUCTION TEST
To determine the ability of some microbes to reduce nitrate(NO3
- ) to nitrites(NO2
-)
or beyond the nitrite stage.
MEDIA : Nitrate broth – Potassium nitrate
REAGENTS : Alpha-naphthylamine (Reagent A) & Sulfanilic acid (Reagent B)
PRINCIPLE :
NO3
- NO2
- N2
If nitrite(NO2
-) is formed, then
NO2
-
Nitrate reductase Other enzymes
+ reagent A + reagent B Sulfobenzene azo-alpha
(colorless) naphthylamine
Eg: E.coli, S. aureus (red coloured)
If nitrogen gas(N2) is formed Colourless reaction
If the organism is non reducer Colourless reaction
To differentiate these two cases, add zinc powder.
Zinc powder can reduce nitrate to nitrites.
17. • If organism reduced nitrate to nitrogen gas, then there are no nitrates present
and the addition of zinc dust will have no effect. Hence the test is positive and
gives colourless reaction the organism is a REDUCER
• If nitrates were not reduced then zinc will reduce them to nitrites. Nitrites will
react with 2 reagents and give a red colour. Test is negative and organism is NON
REDUCER. Eg: N.gonorrhoeae
Nitrate broth
Zinc powder
Nitrogen gas
/non reducer
Nitrogen gas
Reducer
Non reducer
18. UREASE TEST
To determine the ability of microbes to degrade urea by urease.
MEDIA : Christensen’s Urea agar
REAGENTS : Phenol red
PRINCIPLE :
Urea + 2 H2O CO2 + H2O + 2 NH3
Ammonia increases the pH which can be detected by pH indicator
Urease
POSITIVE : Pink colour is observed
Eg: Proteus
NEGATIVE : No colour change
Eg: E.coli
19. OXIDASE TEST
To determine the ability of microbes to produce oxidase enzyme.
REAGENT : 1% Kovacs reagent (tetra methyl para phenylenediamine dihydrochloride)
PRINCIPLE :
• Cytochrome C oxidase is an enzyme that facilitates transfer of electrons to
oxygen in aerobic bacterial respiratory transport system.
• Here the oxidase reagent substitutes as the electron acceptor.
Kovacs reagent Indophenol
(colourless oxidase reagent) (purple colour)
Cytochrome oxidase
POSITIVE : Purple colour is observed
Eg: Pseudomonas
NEGATIVE : No colour change
Eg: E.coli, S. aureus
20. CATALASE TEST
To determine the ability of microbes to produce catalase enzyme
REAGENT : Hydrogen peroxide
PRINCIPLE:
• During respiration many microbes produce byproducts that are toxic to cells
like Hydrogen peroxide(H2O2)
• To neutralize this toxin microbes produce an enzyme CATALASE
2 H2O2 2 H2O + 02 (gas bubbles)
POSITIVE : Presence of effervescence
Eg: E.coli, S.aureus etc
NEGATIVE : No effervescence
Eg: Streptococcus
Catalase
21. OXIDATIVE – FERMENTATIVE TEST (OF TEST)
To differentiate between oxidative and fermentative bacteria
MEDIA : Hugh Leifson’s OF media (high glucose & low peptone)
INDICATOR : Bromothymol blue
PRINCIPLE :
• Under anaerobic condition(overlay with a layer of oil), fermentative organisms
covert glucose mixed acids.
• Under aerobic condition, non-fermenting(oxidative) organisms produce small
amount of weak acids.
• The decrease amount of peptones and increase amount of glucose facilitates
detection of weak acids.
• Acid decreases the pH which can be detected by pH indicator which changes
the colour from green to yellow.
Examples: Oxidative – Pseudomonas aeruginosa
Fermentative - E.coli
Non saccharolytic - Alcaligens faecalis
23. ONPG TEST FOR β-GALACTOSIDASE
To determine the presence or absence of the enzyme β-galactosidase
MEDIA : ONPG broth
PRINCIPLE :
• β – galactosidase is an enzyme that converts
Lactose Galactose + Glucose
• O – Nitro – β – D – galactopyranoside is structurally similar to lactose except that
orthonitro phenol has been substituted for glucose.
Onpg(colourless) Galactose + orthonitro phenol(yellow)
galactosidase
galactosidase
POSITIVE : Yellow colour observed
Eg: E.coli
NEGATIVE : No colour change
Eg: Proteus vulgaris
24. COAGULASE TEST
This test is used to identify Staphylococcus aureus (positive) from Coagulase
negative S.aureus and other microbes.
• Coagulase is an enzyme that convert fibrinogen in plasma fibrin
S.aureus
SLIDE TEST
• Heavy suspension of organism made on glass slide and mixed with a drop of
plasma.
COAGULASE POSITIVE : Macroscopic clumping in 10 seconds or less in coagulated
plasma drop and no clumping in saline.
Bound coagulase (SLIDE TEST)
Free coagulase (TUBE TEST)
25. COAGULASE NEGATIVE : No clumping in either drop.
• Negative results should be confirmed with tube coagulase test.
TUBE TEST
• A suspension of organism is suspended and incubated with plasma at 370C
COAGULASE POSITIVE : Clot of any size is observed.
Eg: S.aureus
COAGULASE NEGATIVE : No clot (plasma remains wholly liquid or shows only a
flocculant or ropy precipitate)
Eg: S.epidermidis, E.coli
26. GELATINASE TEST
To determine the ability of an enzyme to produce the enzyme gelatinase that
hydrolyze gelatin
MEDIA : Gelatin medium – gelatin, peptone, beef extract
PRINCIPLE :
Gelatin Polypeptides Amino acids
• If the organism produce gelatinase, then it will liquefy the medium.
gelatinase gelatinase
POSITIVE : Partial or complete
liquefaction
Eg: Aeromonas hydrophila
NEGATIVE : No liquefaction
Eg: E.coli
27. STARCH HYDROLYSIS TEST
To determine the ability of an organism to produce the enzyme amylase and
hydrolyze starch.
MEDIA : Starch agar – nutrient agar + starch
INDICATOR : Iodine solution (Grams iodine)
PRINCIPLE :
The starch molecule consists of two constituents:
Amylose, an unbranched glucose polymer
Amylopectin, a large branched polymer
Both amylose and amylopectin are rapidly hydrolyzed by certain bacteria using
enzymes called α-amylases.
Starch Dextrin + Maltose + Glucose
(Amylose + Amylopectin)
α - amylase
28. POSITIVE : If the organism has produced amylase, will hydrolyze starch and a
clear area appears after adding grams iodine.
Eg: Bacillus subtilis, B.megaterium
NEGATIVE: Absence of clearing after adding grams iodine, no starch hydrolysis.
Eg: Staphylococcus epidermidis, S.agalactiae
29. API STRIPS – RAPID TESTS
(Analytical Profile Index)
• Commercial miniaturized biochemical test panels – cover a significant number
of clinically important groups of bacteria as well as food and water associated
microorganisms.
• Different test panels are prepared in dehydrated forms which are reconstituted
upon use by action of bacterial suspensions.
• After incubation, positive test results are scored as a 7 digit number (profile).
• Identity of the bacterium is then easily derived from the database with the
relevant cumulative profile code book or software.
31. AUTOMATED IDENTIFICATION SYSTEM
• Offer greater accuracy and increased speed identification over manual
methods.
• MicroScan Walkaway & Vitek 2 – two very popular automated identification
system.
• Both have used convectional panels with instruments that can read and
interpret panel results, perform antibiotic susceptibility tests and print results
without human intervention.
VITEK - 2
