Klebsiella species are cytochrome oxidase negative and catalase positive. Other typical Enterobacteriaceae taxonomical tests vary among the species: indole, methyl red, Voges–Proskauer and Simmons citrate. They are usually lysine decarboxylase positive and ornithine decarboxylase negative.

Is Klebsiella catalase negative?

Klebsiella aerogenes, previously known as Enterobacter aerogenes, is a Gram-negative, oxidase negative, catalase positive, citrate positive, indole negative, rod-shaped bacterium.

Is Klebsiella pneumoniae Gram positive or negative?

Klebsiella pneumoniae is a gram-negative, lactose-fermenting, non-motile, aerobic rod-shaped bacterium. It has been a known human pathogen since it was first isolated in the late nineteenth century by Edwin Klebs. The microbiology, pathogenesis, and epidemiology of infections due to K.

Is Klebsiella coagulase positive or negative?

The bacteriemia was mostly caused by coagulase-negative staphylococcus. Infections of the urinary tract were caused by gram-negative bacteria Klebsiella pneumoniae and Escherichia coli. Other infections were caused by coagulase-negative Staphylococci, Staphylococcus aureus, Klebsiella pneumoniae and Escherichia coli.

Is Klebsiella pneumoniae Onpg positive?

The plant pathogenic Klebsiella pneumoniae strain Borkar was positive for ONPG, lysine utilization, urease, VP, MR, PYR, esculin hydrolysis, nitrate reduction, citrate utilization and utilization of sucrose, sorbitol, trehalose, malatiose, salicin, mannose, glucose, malonate, arabinose, rhamnose and manitol as …

Is Pseudomonas Gram positive or negative?

Pseudomonas species are Gram-negative, aerobic bacilli measuring 0.5 to 0.8, μm by 1.5 to 3.0 μm. Motility is by a single polar flagellum.

Is Klebsiella pneumoniae citrate positive or negative?

Klebsiella pneumoniae and Proteus mirabilis are examples of citrate positive organisms. Escherichia coli and Shigella dysenteriae are citrate negative.

Does Klebsiella pneumoniae grow on MacConkey Agar?

Klebsiella pneumoniae is a Gram-negative, non-motile, encapsulated, lactose-fermenting, facultative anaerobic, rod-shaped bacterium. It appears as a mucoid lactose fermenter on MacConkey agar.

Is Klebsiella oxytoca oxidase positive or negative?

Klebsiella species also have negative cytochrome oxidase reactions, ferment lactose, produce acid slants and butts with gas production on triple sugar iron reaction, grow on Simmons citrate agar, and are nonmotile.

Which carbohydrate can Klebsiella pneumoniae ferment?

As glucose, xylose, and arabinose are the primary components of lignocellulose hydrolysates [28], it is presumed that K. pneumoniae has great potential to ferment lignocellulosic hydrolysates into valued products.

Article first time published on

Does Klebsiella pneumoniae grow on nutrient agar?

Selective media for Klebsiella pneumoniae have been important in studies of hospital-acquired infections. On an agar medium which included ornithine, raffinose, and Koser citrate, K. pneumoniae strains grew as yellow mucoid colonies at 24 h and there was some increase in colony size at 48 h.

How is Enterobacter different from Klebsiella?

can be differentiate based on sensitivity patterns. Most Klebsiella strains are susceptible to cephalothin, and all are sensitive to colistin. Enterobacter strains were resistant to cephalothin but susceptible to colistin.

Is Klebsiella methyl red positive?

Positive (turning red): E. coli, Edwarsiella, Shigella, Salmonella, Citrobacter, Proteus, Klebsiella ozoenae, Klebsiella rhinoscleromatis, Yersinia. Negative (turning yellow): Enterobacter, Hafnia, Serratia, Klebsiella pneumoniae.

Does Klebsiella pneumoniae ferment mannitol?

Standard K. pneumoniae cultures showed positive reaction for urease production, citrate utilization, catalase reaction and fermentation of sugar like glucose, lactose sucrose, mannitol, adonitol, melibiose and esculin.

Is Pseudomonas aeruginosa indole positive?

Pseudomonas gives negative Voges Proskauer, indole and methyl red tests, but a positive catalase test. While some species show a negative reaction in the oxidase test, most species, including P.

Is Klebsiella gram negative bacilli?

Klebsiella [kleb−see−ell−uh] is a type of Gram-negative bacteria that can cause different types of healthcare-associated infections, including pneumonia, bloodstream infections, wound or surgical site infections, and meningitis.

Does Klebsiella pneumoniae hydrolyze starch?

Starch hydrolysis: No clear zone around E-coli, Klebsiella pneumoniae and Staphylococcus aureuswere observedindicating negative result.

Is Pseudomonas fluorescens gram-positive?

Pseudomonas fluorescens are Gram-negative bacteria that have diverse lifestyles and versatile metabolisms. These bacteria are found in decaying and living plants, soil, and water. Some P.

Is Pseudomonas prokaryotic or eukaryotic?

Background. The genome of Pseudomonas aeruginosa contains at least three genes encoding eukaryotic-type Ser/Thr protein kinases, one of which, ppkA, has been implicated in P. aeruginosa virulence.

Is Pseudomonas aerobic or anaerobic?

Pseudomonas aeruginosa had been considered as an obligately aerobic bacterium previously, but it is now recognized to be highly adapted to anaerobic conditions. Because the P. aeruginosa-infected mucus in the CF airway is depleted of oxygen, the anaerobic physiology of P.

Is Klebsiella oxytoca catalase positive?

K. oxytoca is a facultative anaerobe (4) that can fix nitrogen (7) and hydrolyze cellulose (3). It is both catalase positive and indole positive (8).

Is Klebsiella Mr positive?

Note: A culture will usually only be positive for one pathway: either MR+ or VP+. Escherichia coli is MR+ and VP-. In contrast, Enterobacter aerogenes and Klebsiella pneumoniae are MR- and VP+. Pseudomonas aeruginosa is a glucose nonfermenter and is thus MR- and VP-.

Is Escherichia coli oxidase positive?

E. coli bacteria are among the few species of lactose (LAC)-positive, oxidase-negative, gram-negative rods that are indole positive.

Can gram positive grow on MacConkey Agar?

No colonies: Gram-positive bacteria will not form any colonies on MacConkey medium.

Is Klebsiella pneumoniae beta hemolytic?

Colonies are without hemolysis but many strains isolated from infections are beta-hemolytic. Fig. 9 Klebsiella pneumoniae. Non-hemolytic (gamma-hemolytic), mucous colonies of Klebsiella pneumoniae on blood agar.

Is Klebsiella pneumoniae an opportunistic pathogen?

Some strains of K. pneumoniae act as opportunistic pathogens, infecting critically ill and immunocompromised patients. These K. pneumoniae are a common cause of health-care associated infections including pneumonia, urinary tract infections (UTIs), and bloodstream infections.

What does Klebsiella look like on agar?

Laboratory Identification of Klebsiella pneumonia colonial morphology on blood agar is mucoid and 3 to 4mm in diameter. On MAC, K. pneumoniae colonies are pink (LF), mucoid (usually), and 3 to 4 mm in diameter. Colonies on Hektoen enteric agar and XLD are yellow.

Why does Klebsiella pneumoniae show mucoid colonies?

Klebsiella are ubiquitous and may colonize the skin, pharynx, or gastrointestinal tract in humans. They form large moist colonies due to “large mucoid polysaccharide capsule (K antigen) that protects from phagocytosis and aids in adherence” (U of Maryland).

What is the difference between Klebsiella aerogenes and Klebsiella pneumoniae?

Classification. The name Klebsiella aerogenes was originally used for the non-motile, capsulate, gas-producing strains commonly found in human faeces and in water; certain biochemically atypical Klebsiella strains isolated from the respiratory tract of man and animals were designated K. pneumoniae.

How do you differentiate Enterobacter and Serratia?

Thus, a rapid test has been needed to differentiate Serratia from Enterobacter. Serratia produces the blue-green indigo color within 5 min., whereas Enterobacter produces the blue-green color in half an hour.

Is Enterobacter encapsulated?

A gram-negative rod shaped motile and encapsulated bacterium and have peritrichous flagella that surrounds outer surface involved in nosocomial infections.