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1. A toxin identical to diphtheria toxin is produced by many strains of ………..

a. P.aeruginosa b. Pr.mirabilis

c. Y.enterocolitica d. F.tularensis

2. New born infants may develop meningitis when infected with K1 antigen bearing strains of ….

a. E.coli b. Pr.vulgaris

c. S.marcescens d. K.pneumoniae

3. Pontiac fever is best diagnosed by ……..

a. culturing Legionella from blood samples

b. detecting Legionella antigen in urine

c. identifying rise in titre of antibody to Legionella in a convalescent serum sample

d. identifying rise in titre of antibody to Legionella during first week of infection

4. Lyme disease is usually acquired via bite of …….

a. larva of Ixodes tick b. nymph of Ixodes tick

c. adult of Ixodes tick d. adult of Dermacentor tick

5. The lack of tolerance of strict anaerobes to molecular oxygen is attributed to their ……

e. lack of cytochromes

f. lack of superoxide dismutase &/or catalase

g. lack of Kreb’s cycle

h. lack of peptidoglycan in cell wall

6. Cr.gattii is differentiated from other two varieties of Cr.neoformans by producing cobalt blue color colonies on …….

a. L-Canavanine Glycine Bromothymol Blue Agar

b. Creatinine Dextrose Bromothymol Blue Agar

c. Niger seed agar

d. Christensen’s urea agar

7. Rodents serve as human reservoir for infection in ……….

a. Interstitial pneumonia b. Cryptococcosis

c. Coccidioidomycosis d. Dermatophytosis

8. S.Typhimurium used as a carrier for ……… vaccination

a. Penicilliosis b. Pneumocystosis

c. Coccidioidomycosis d. Paracoccidiodomycosis

9. The fungus which have predilection to vasculature is ……..

a. Aspergillus b. Zygomycetes

c. Candida d. Penicillium

10 ……… produce red fluorescence on wood’s lamp examination

a. Corynebacterium minutissimum b. Microsporum

c. Trichophyton d. Malassezia furfur

- Quiz compiled by Ms. Sweetha

Enter your answers in Comments section or email to Invisibleyetinvincible@gmail.com.Surprise Gifts await the first three all- correct entries.

Keywords: Microbiology Quiz, Microbiology MCQs, Medical Micro Quiz

All these are facts most of us can perceive ‘inside’ but feel bitter to explicitly ‘speak out’!

1. We are poor in planning: Most of our Indian professors are still reeling with 'old-world' techniques and are not good at updating! They spend their time in having coffee and waste time in politicising whatever they came across! They hardly find time to update technological innovations and are in a 'bad-mood' to experiment new things! All because they have limited funding and they 'channelise' the funding and so cannot think about 'high-impact-science' articles!

2. Most of our Indian professors are poor in English: Our professors cannot speak/understand/write good English! They are good at criticizing others but they themselves aren't aware that their backyards are 'soiled'! They hardly think about participating in 'high-wire journal clubs' and are concerned always about sending their students to 'pay their personal electricity bills, sending their students to 'buy good quality rice, pepper and sometimes washing their cars and sometimes even dropping their children at school. Some want their students to 'pick them up' every morning from home and some want their students to get tea and snacks from a high quality restaurants! (if he/she doesn't abide his/her life will be shattered 100%) How can you expect a nobel prize?

3. Our infrastructure is poor: Although just a delay in procuring the chemicals required for experiments we cannot say that our research is poor! The net outcome within a particular duration matters! Our infrastructure has to be refurbished! All old instrumentations and 'glasswares' need to be replaced with state-of-the-art automated polypropylene instruments! Technicians need to be trained with updated technical expertise!

4. Bribe in university appointments: How can one anticipate nobel prize in a country with their high-level university administration involving themselves in bribe? How is this possible?? Right from the appointment of a peon to the ‘highest-level’ recruitment our system is handicapped with 'corruption'! Yes, we stand in the 80’s after the 'very-poor' African countries in corruption! Pathetic! Can you ever dream a nobel?

4. Most are back-pullers in India: This is the reason why most of our Indian brothers go abroad where there are 'very-few and rare-back-pullers'! One man cannot tolerate others growth! Never in India!! And the other guy cannot be tolerant enough always to 'feel the pinch' given by the 'back-puller'! A fellow Indian will 'pull down' the 'other person's' leg everytime he tries to win a prize! Ask yourself if it’s true!! This is there right from private to government systems, everywhere 'in India' except a very few people who really cares for you! Will you ever dream a Nobel prize in India???? Will you??? No...Never...ever!!!

5. A student cannot propose a new concept to his superior: Never! He will be banged! 'Do what I say!!...You are not the boss....(But when he went to his boss his boss never knew how to calculate volume and concentration!!!)! If he/she ever complained this to someone he/she will be warned that 'you cannot survive anywhere'! My god, can we dream of Nobel laureates? Never...

6. You can never speak out: Dictatorship is the most common thing you get to see in most of the Indian institutions! You could hardly speak to your institute director! Why because he is always busy or he has many 'sub-ordianates' who could help you solve the problem! Every citizen has the right to live and speak out what is wrong and where the glitch is!! We hardly have the right to speak!! And we hardly speak to our inferiors! Imagine (including recent Nobel awardee, Dr. Ramakrishnan) it's all your students and postdocs who got you this laurel (of course you acknowledged this at Karolinska..)! Acknowledge due credit to your students always, be it your master students, your postdocs and even your peons and personal attendants....should one day this 'otherwise-rare-thing' to happen! It’s all your hard-work, perseverance, prayers, obedience, equality, mutual respect and more importantly 'human-values' that will gradually bring our country on top! And as far as an Indian student could perceive, Nobel prize is for NOBLE people who live and toil in SCIENCE for years and decades and not for us ' Indians' who hardly find time to sit and think and write grants! Lets feel proud that this Prof. Ramakrishnan during his student tenure ‘managed’ to escape from the corrupt Indian system, from back-pullers and so so... to win this feat!

Sorry, if I had hurt someone so badly!!! This is the truth! Ask your conscience, if I am right!!!

- Dr. E.M. Shankar

Proteus, belonging to the tribe Proteae, is a part of normal gastrointestinal flora, widely distributed in nature as saprophytes. These bacteria are non capsulated, motile rods by peritrichous flagella. They exhibit a wide range of biochemical and antigenic heterogenicity. They are causative agents for urinary tract infection, wound infection and pneumonia. The genus Proteus includes two species of clinical importance – P.mirabilis and P.vulgaris. They grow on almost all simple media and easily identified by its swarming motility and fishy odor.

SWARMING:

A notable property of Proteus is the ability to swarm on solid media. Discrete colonies are seen in young cultures but thereafter actively motile cells spread on the surface of plate in successive waves to form a thin layer in concentric circles.

WHY DO THE PROTEUS SWARM ?

Swarming takes place in a discontinuous manner each period of outward progress followed by a stationary period.

# multinucleate cells (swarm cells) synthesis numerous number of flagella

# acidic polysaccharide slime helps in swarming

# negative chemotactic factors accumulate during growth

# moisture on agar surface

swarming growth is a problem in the laboratory when mixed growth is obtained in which Proteus bacilli overgrown with other bacteria.

METHODS TO PREVENT SWARMING:

Several methods have been devised to inhibit swarming of Proteus.

1. AGENTS WHICH ALTER GROWTH CHARACTERISTICS:

Ø Bile salts in Mac Conkey agar inhibits growth of Proteus

Ø Sodium azide in a concentration of about 1:500- inhibits growth

2. INHIBITION OF MOTILITY:

Ø Increase in concentration of agar upto 6% inhibits migration of Proteus and consequently isolated colonies are formed.

Ø 0.02% tannic acid –tannic acid binds to outer membrane of cell wall inhibiting the movement of flagella.

Ø 20mM salicylate decreases motility of Proteus.

3. AGENTS WHICH ACT ON FLAGELLA PRODUCTION:

Ø Incorporation of Boric acid – 1:1000 form complex with flagellin and cause disintegration of flagella. Thus inhibiting migration and prevent swarming.

Ø 1x10⁶ Plaque forming units/ml – Phage X₇ is a flagellotropic phage for Proteus.

Ø The addition of 0.2 ml of phage spread over the surface of agar plates and immediately immobilizes the Proteus.

Ø In fish meal extract agar with NaCl swarm cells were not formed due to deficiency of glutathione, viscous environment and flagella rotation inhibition.

Ø Effect of sodium tetradecyl sulfate immobilizes the strain by inhibition of flagella formation or by some lytic action on flagella.

Ø Phenyl ethyl alcohol – concentration of 5 to 6% impairs flagella function but leaves the flagellum morphologically intact.

Ø Addition of ferrous salts to protease peptone medium inhibits flagellar function without affecting growth of the organism.

4. DEFICIENCY OF ELECTROLYTES:

Ø Cystine Lactose Electrolyte Deficient medium (CLED) – peptone base agar with lactose and L-cystine restriction of electrolytes inhibits swarming of Proteus.

5. OTHERS WHICH PREVENT SWARMING:

Ø Media containing activated charcoal (1% w/v charcoal in nutrient agar base) inhibits swarming but not the growth of Proteus. The suppression depends on the concentration of charcoal in medium. It does not interfere with flagella production.

Ø Chloral hydrate and Sulphonamide inhibits swarming when added to media.

Ø Predried plates with para nitro phenyl glycerine inhibits swarming without imparing motility. It has long shelf life, heat stable and convenient to use in preparation of media.

Ø Sodium desoxycholate - Leifson BD desoxycholate agar prevents swarming

Ø Anionic detergents such as sodium alkyl sulfate in concentration of 0.1m mol/L without affecting its growth

Ø Selective Proteeae medium (SPM) contains tryptose phosphate agar, phenolphthalein monophosphate, bile salts and polymixin B – inhibits swarming.

Ø Bismuth Sulphite in Wilson Blair medium.

Ø Use of monopterenes (terpenes & terpenoids) and psychotropic drugs (serotonin & sertalin) inhibit swarming of Proteus.

- Ms. Sweetha & Ms. Subha

Keywords: Proteus, Swarming motility, Proteus mirabilis, Proteus vulgaris, Swarming Proteus

International seminar on

"New Insights in the Management of Antibiotic Resistance -NISMAR2009"

Organized by

Department of Microbiology

Dr. A.L.M Post Graduate Institute of Basic Medical Sciences

University of Madras

Taramani

Chennai - 113.

• International Seminar Venue: Triple Helix Auditorium CLRI Campus Adayar

• To Download Registration form: Click Here! or Download

• To Download Scientific Sessions: Click Here! or Download

• Last date for Registration: 20October 2009

• Last date for Submitting abstract for poster presentation: 20October 2009

• Date of International Seminar: 26th October 2009

Send your filled in registration forms on or before ௨0 October 2009 to

Dr. Padma Krishnan

Organizing secretary

NISMAR2009

Assistant Professor

Department of Microbiology

Dr. A.L.M Post Graduate Institute of Basic Medical Sciences

University of Madras

Chennai - 113.

For More Details: Contact us at nismar2009@gmail.com or Call: 9840742105

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