Category Archives: Bacteriology

Morphology of bacteria

Bacterial cells are between 0.3 and 5lm in size. They have three basic forms: cocci, straight rods, and curved or spiral rods. The nucleoid consists of a very thin, long, circular DNA molecular double strand that is not surrounded by

Pathogen Terminologies

Infectiological Terminology I (Pathogen) Term and Explanation Saprophytes These microorganisms are nonpathogenic; their natural habitat is dead organic matter. Parasites Unicellular or metazoan organism living in or on an organism of another species (host) on the expense of the host


Clostridium difficile (PSEUDOMEMBRANOUS COLITIS) Clostridium difficile causes antibiotic-associated diarrhea (AAD) and more serious intestinal conditions such as colitis and pseudomembranous colitis in humans. These conditions generally result from overgrowth of Clostridium difficile in the colon, usually after the normal intestinal


Clostridium botulinum (BOTULISM) It is a serious paralytic illness caused by Clostridium botulinum. The toxin (only types A, B, E and F cause illness in humans) binds to receptors on peripheral nerves, where acetylcholine is the neurotransmitter and inhibits nerve


Clostridium perfringens (GAS GANGRENE) Clostridium perfringens, a gram positive rod, causes wound colonization (gas gangrene) after soil, and to a lesser extent intestinal tract, contamination. The organism produces several tissue degrading enzymes (including lecithinase [alpha toxin], proteolytic and saccharolytic enzymes).


Clostridum tetani (TETANUS) Clostridium tetani, a Gram-positive rod that forms a terminal spore, is commonly found in the soil, dust and animal feces. Contamination of wounds, which provide anaerobic conditions, can lead to spore germination and tetanus, a relatively rare,

Bacteria Organisms

Types of bacteria and their economic importance Helicopter pylori which causes Ulcer. Vibro Cholerae which causes Cholera. Neisseria meningitidis which causes Meningitis. Treponema palladium which causes Syphilis. Bacillus anthracis which causes a common disease of livestock and human. Clostridum tetani

20 Types of Bacteria and Shape

COCCUS(spherical shaped bacteria) 1)Staphylococcus aureus 2)Staphylococcus epidermidis 3)Staphylococcus horminis 4)Staphylococcus pneumoniae 5)Staphylococcus haemolytical BACILLUS(rod shaped bacteria) 1)Lactobacillus specie 2)Listeria monocytogenes 3)Escherichia coli 4)Proteus specie 5)Enterobacter cloacae SPIRILLUM (spiral shaped bacteria) 1)Treponema pallidium 2)Treponema carateum 3)Treponema dentical 4)Spirillum minus 5)Fusobacterum necrophorum


These are important anaerobic covering, and it is made up of a gas tight chamber with cemented covering portal and an inlet lock for moving substance in or out the chamber. The gas usually oxygen free is expelled via the


SEMI-SOLID INDICATOR Some anaerobic jar is made up of side arm; this side arm is a point at which indicator tube is attached to the jar via a short length of rubber tubing. This type of jar have their own


THESTING ANAEROBIC JAR There are two purposes which can cause anaerobic jar not to function properly, which are; Leakage jar: when there is leakage in the jar, there is possibility of the jar not to function normally. These conditions can


ANAEROBIC INCUBATION IN CANDLE JAR When micro organism is important to grow in an atmosphere CO2, the easiest way is to place the plate culture together with a light candle and crew down the lid of the jar and incubate,


BIOLOGICAL EXAMINATION OF SPECIMEN Any sample sent for screening in the microbiology laboratory must be handle with extreme care because the sample may have biological pathogens that may cause disease to the lab personnel or may even spread to the


HOW TO HANDLE HIGH RISK SAMPLE High risk sample can be define as a sample that is suspected to carry the following high risk infections, such as HIV, HBsAg, Tuberclosis etc High risk sample like the one stated previously or


The following characteristic must be figure out when examine specimen microscopically; Colour Opacity Consistency Present of blood Pus or mucus Present of parasite, fungi, and bacteria Culture plate: type of colonies number seen either  1, 2, 3, or so on

Blood Culture

Blood culture: many thought must be put in mind when designing or adopting a reliable method, such thought are       The volume of the blood, it should be born in mind that high volume of blood faster high growth of

Automated blood culture

Automated blood culture  Automated blood culture: there are several methods developed for the automatic detection of bacteria growth in a medium. Most but all of this method depend on the obtaining of different source of metabolites, these takes place in

Cerehrospinal fluid

Cerehrospinal fluid examination  Cerehrospinal fluid: when the sampes is brought into the clinics it is necessary that the clinicians should be notified instantaneously for the organism that is suspected to be present in the sample. The sample is generally sent

Gram Negative Bacilli Method

Gram Negative Bacilli Method A loopful of stool should be inoculated into a plate of deoxycholate citrate agar and tube of selenite and incubate at 35ºC of temperature. Campylobacters palte should be also inoculated and incubate in 5%CO2 /N2  atmosphere

Fluid Examination in the Laboratory

Fluid Examination in the Laboratory Macroscopy, such as the appearance of the fluid should be noted. Transfer the fluid to clean sterile centrifuge container or tube, and centrifuge the fluid for 5 minute at 3000rpm. Discard the supernatant, then the

Pus(Abscesses) Examination

PUS(Abscesses) Pus: pattern of screening these specimen depend on the part of the body which the specimen where collected, either the specimen is from boil, ear, skin wound e.t.c. the specimen can be message on a sterile container or swab

sputum examination

Sputum: these examination may classified into two groups the one for examination of mycobacterium turberculosis and the sencon for examination of normal mouth flora such as; Neisseria Diptheroids Spirochates Fusiform bacilli Non haemolytic streptococcus Step for examination of Normal Flora

Genitourinary Swab Sample

Genitourinary Swab Sample These swabs are mostly collected from genital organ, the sample is specifically collected incase of suspicion of genital infection, the suspected microorganism that cause genital infection; Trichomoniasis Puerperal sepsis Gonorrhea Escherichia coli Staphylococcus  aureus e.t.c. These swabs

Examination of Mycobacterium Tuberculosis

Examination of Mycobacterium Tuberculosis The smear from the sputum can be make for demonstration of the present acid bacilli, but cannot be used for examination of turbercle bacilli. Petroff’s Method for Examination Of M.T mix the sputum with sodium hydroxide

Laryngeal Swab for Mycobacterium Tuberculosis

Laryngeal Swab for Mycobacterium Tuberculosis As the name implied, the sample is usually collected from larynx for examination of mycobacterium tuberculosis. It has two method of culturing  the sample; Is an absorbent wool swabs Alginate wool swabs Method 1. Absorbent

Staphylococcus areaus on a blood agar after 48hours Incubation

HVS M/C/S Bellow is the picture of the growth of Staphylococcus areaus of High vaginal swab microscopic culture and sensitivity. After 48hours of incubation bellow is the growth of microorganism isolated, with sensitivity. How to read the result First thing


Hexoses, such as the ones illustrated here, have the molecular formula C6H12O6. German chemist Emil Fischer (1852-1919) identified the stereoisomers for these aldohexoses in 1894. He received the 1902 Nobel Prize for chemistry for his work. that have opposite configurations

Deoxycholate Citrate Agar

Deoxycholate Citrate Agar These media composed of; Agar Neutral red Meat extract Sodium deoxycholate Lactose Proteose peptone Ferric citrate Sodium citrate Sodium thiosulphate Preparation strictly on manufacturer instruction These media is used as a selective media for examination and identification

MacConky Agar

MacConky Agar  These media composed of; Sodium chloride Lactose Neutral red Agar Peptone Sodium taucholate The media should be prepared via manufacturer instruction. These media is used for differentiating intestinal organism into pathogen and non pathogenic fermenter micro organism, the


Bacteriophage is the term referred to a virus that used bacteria as their host. Bacteria creates two types of toxin which are: Exotoxin Edotoxin Exotoxin A component of toxin obtained from gram negative bacteria cells envelop, the cell envelope is


PEPTONE WATER This is water that is use for examination of water sugar called peptone water sugar. The water is for preparation of sugar media and also used for cultivation of vibro cholerae. These can take place when the sugar


Nutrient Broth Nutrient Broth: these media is used for growing fastidious bacteria that is an organism that is not too difficult to cultivate. These media are basal media, in such case use as basal media for blood agar in the

Culture production evolution

On the origin of bacteriology, the culture media used by then are ox Heart or Calf brain. But with the advancement of knowledge of bacteriology, this type of media is drastically disappearing in the microbiology world, and is been replace


There are varieties of fault found in culture media mostly when preparation of dehydrated media is in progress such as; Inappropriate weigh, inaccurate measure of water: this problem take place as a result of faulty calibration of weighing balance, and

Culture production evolution

On the origin of bacteriology, the culture media used by then are ox Heart or Calf brain. But with the advancement of knowledge of bacteriology, this type of media is drastically disappearing in the microbiology world, and is been replace


For isolation of a single colony, there are step required to inoculate the petri dish before the mission can be accomplished. The steps are; Sterile wire loop, take a loopful specimen and inoculate over area A. Sterilize the wire loop

Microbiology cultural techniques

TUBE CULTURE TECHNIQUE This culture technique involved the following; stop culture, deep culture and roll culture. Slope Culture: several test technique is used to classified micro organism preferably on solid medium, slope culture is one of the method mostly for

Use of petri dish for culturering

In other to study the features and the characteristics of micro organism colonies, petri dish is the apex apparatus used for the task. Petri is shallow, flat and have a large surface area. These fixtures make it possible growth of


required environment to store prepared media Just like order substance in the laboratory like the way we store chemicals, which chemical have there own environment which they can be stored, so do prepare me that has their required environment to


Media is group in to two which are; Liquid media, and solid media. Liquid media: as the name implied, these types of media are liquid in nature, they are used to culture many micro organism. The organism growth on these


HYDROGEN ION CONCENTRATION This is the acidic or basic content required by the micro organism to growth. The PH of bacteria varies, some required acidic environment before they can growth, some other required basic environment before they can growth. But


These mean the status which the media must ascertain before they can support the growth of bacteria, moisture, carbon, and nitrogen substance are very essential for artificial media to meet there requirement in other to support the growth of micro


Culture media Cultue media: is a simple and artificial food which micro organism required for it growth. Before organism can be study, it must first of all be culture and isolated, this occur by studying the anatomy and physiology of


CONTROL OF FILTRATION PROCESS This simply means the process where filtration is directed to achieve a satisfactory result of filtration. In filtration there are some challenge face, this can be overcome by testing the filtration challenge. This can be done


STERILIZATION BY FILTRATION The first approach on how to purify water where carried out by allowing water to pass through a bed of sand gavel and cinders. But as the knowledge of bacteriology and realization of the association of water


GASEOUS STERILIZATION There are some chemical substances which are gaseous in nature that are used in the laboratory for sterilization i.e formaldehyde and ethylene oxide. This substance is used as an alternative when autoclave is not available. Formaldehyde is use