What Gram negative bacteria does not ferment lactose?
What Gram negative bacteria does not ferment lactose?
Non lactose-fermenting (Lactose negative): ● Oxidase (-): Acinetobacter spp, coli, Proteus spp, Salmonella spp, Shigella spp, Serratia spp*, Stenotrophomonas maltophilia ● Oxidase (+): P. aeruginosa, Aeromonas spp.
Do gram negative bacteria ferment lactose?
Using neutral red pH indicator, the agar distinguishes those Gram-negative bacteria that can ferment the sugar lactose (Lac+) from those that cannot (Lac-). This medium is also known as an “indicator medium” and a “low selective medium”. Presence of bile salts inhibits swarming by Proteus species.
Are Gram-negative rods catalase positive?
Gram-positive cocci include Staphylococcus (catalase-positive), which grows clusters, and Streptococcus (catalase-negative), which grows in chains. The staphylococci further subdivide into coagulase-positive (S. aureus) and coagulase-negative (S.
Is E. coli oxidase-positive or negative?
E. coli bacteria are among the few species of lactose (LAC)-positive, oxidase-negative, gram-negative rods that are indole positive. Due to the infrequent isolation of non-E.
Is E. coli catalase-positive or negative?
Biochemical Test and Identification of E. coli
| Characteristics | E. coli |
|---|---|
| Catalase | Positive (+ve) |
| Oxidase | Negative (-ve) |
| MR | Positive (+ve) |
| VP | Negative (-ve) |
Is Serratia marcescens catalase positive or negative?
Biochemical Test and Identification of Serratia marcescens
| Basic Characteristics | Properties (Serratia marcescens) |
|---|---|
| Capsule | Negative (-ve) |
| Catalase | Positive (+ve) |
| Citrate | Positive (+ve) |
| Flagella | Positive (+ve) |
Is E. coli sulfur positive or negative?
Biochemical Test and Identification of E. coli
| Characteristics | E. coli |
|---|---|
| Nitrate Reduction | Positive (+ve) |
| H2S | Negative (-ve) |
| Gas | Positive (+ve) |
| PYR | – |
Is E. coli gelatinase positive?
The Escherichia coli culture remained solidified indicating that gelatinase was not produced. The red color in the agar is due to the pigment produced by Serratia marcescens.
What does Gram negative rods mean?
Gram negative rods is just one way of describing bacteria that meet certain classifications. Gram stains can be either negative or positive, and rods are long skinny bacteria like two lower case “Ls” put together – like this ll instead of round like cocci, two of which look like this – οο.
What is the treatment for Gram negative rods?
Vancomycin can be used for gram-positive cocci, ceftriaxone for gram-negative cocci, and ceftazidime for gram-negative rods. If the Gram stain is negative, but there is strong clinical suspicion for bacterial arthritis, treatment with vancomycin plus ceftazidime or an aminoglycoside is appropriate.
What is Gram negative rod bacteria?
Acetic acid bacteria – Acetic acid bacteria are rod-shaped Gram negative bacteria. These bacteria are so named as they oxidize ethanol to acetic acid during the process of fermentation, from which they derive their energy. They are present in nature, in flowers and fruits, and are an important part of the food industry.
Is E coli a Gram negative rod?
Escherichia coli (/ˌɛʃəˈrɪkiə ˈkoʊlaɪ/; also known as E. coli /ˌiː ˈkoʊlaɪ/) is a Gram-negative, facultative anaerobic, rod-shaped, coliform bacterium of the genus Escherichia that is commonly found in the lower intestine of warm-blooded organisms (endotherms).