Moraxella (Branhamella) catarrhalis, formerly called Neisseria catarrhalis or Micrococcus catarrhalis, is a gram-negative, aerobic diplococcus frequently found as a commensal of the upper respiratory tract (124, 126; G.
Is Moraxella Gram stain?
Members of the genus Moraxella are Gram-negative, aerobic, asaccharolytic bacteria that can be pleomorphic, resistant to Gram-stain decolorization, and occur predominantly in pairs or short chains.
Is Branhamella Gram positive or negative?
Moraxella catarrhalis, formerly known as Branhamella catarrhalis, is a Gram-negative, aerobic, nonmotile, nonspore-forming, oxidase-positive, and catalase-positive diplococcus.
Is Moraxella a gram-negative rod?
Moraxella organisms are small, gram-negative bacteria that grow well on blood or chocolate agar. They are catalase and oxidase positive. These small diplococci are morphologically difficult to distinguish from Neisseria. Some Moraxella species are gram-negative bacilli.
Is Moraxella catarrhalis viral or bacterial?
Moraxella catarrhalis (M. catarrhalis) is a type of bacteria that’s also known as Neisseria catarrhalis and Branhamella catarrhalis. It used to be considered a normal part of the human respiratory system, but more recent research shows that can it sometimes causes infections.
Why is the Gram stain considered a differential stain?
A differential stain is one that uses 2 or more dyes to distinguish between groups of microbes. The Gram stain is differential based upon the chemical composition of Gram positive and Gram negative cell walls.
How is Neisxeria different from Moraxella?
They can be differentiated from Moraxella and Neisseria species by a catalase test. Most Kingella species are catalase negative; Moraxella and most Neisseria species (except Neisseria elongata) are catalase positive.
What is branhamella Neisseria?
• Branhamella (Neisseria) catarrhalis has been reported as the etiologic agent of serious systemic human infections with increasing frequency. Two cases (pneumonia and septicemia) in which this organism was recovered as the sole bacterial pathogen are described herein.
What is Moraxella catarrhalis infection?
Moraxella catarrhalis is a gram-negative diplococcus that commonly colonizes the upper respiratory tract. It is a leading cause of otitis media in children, acute exacerbations of chronic obstructive pulmonary disease (COPD), and acute bacterial rhinosinusitis.
What types of bacteria are stained differently in the Gram stain?
Due to differences in the thickness of a peptidoglycan layer in the cell membrane between Gram positive and Gram negative bacteria, Gram positive bacteria (with a thicker peptidoglycan layer) retain crystal violet stain during the decolorization process, while Gram negative bacteria lose the crystal violet stain and …
What color do endospores and bacteria stain in an Endospore stain?
green
Whereas the counterstain (safranin) is pink/reddish in color, the primary stain (malachite green) is green in color. Therefore, endospores will appear green in color while the vegetative cells will pink/reddish in color under the microscope.
