Question

The chain of rod shaped bacteria is called-
a. Streptococcus
b. Streptobacillus
c. Staphylococcus
d. Staphylobacillus

Answer 1

Hint: A genus of fastidious gram-negative microaerophilic bacteria, that grow as rods in chains in culture. Tiny, round, convex, greyish, smooth, and glistening colonies. They exhibit a "fried egg" appearance with a thick agar-penetrating centre.

Complete answer:
> Option A is incorrect. Streptococcus contains a chain of coccus bacteria. Streptococcus pneumoniae, for instance. Streptococci are gram-positive aerobic species, including pharyngitis, pneumonia, wound and skin infections, sepsis, and endocarditis, which cause many disorders. For the organ affected, signs differ. Rheumatic fever and glomerulonephritis can be the sequelae of infections due to beta-hemolytic streptococci group A.

> Option B is correct. Streptobacillus constitutes a chain of rod-shaped bacteria or bacilli. Streptobacillus moniliformis, for instance. S. moniliformis is strongly pleomorphic and has been found regularly in the form of filamentous, non-branching chains. For instance, lateral bulbar swellings may grow in the normally straight rod.

> Option C is incorrect. Staphylococcus comprises the grape-like aggregate of coccus bacteria. Staphylococcus aureus, for example. In the family Staphylococcaceae from the order Bacillales, Staphylococcus is a genus of Gram-positive bacteria. They appear spherical (cocci) under the microscope, and form into grape-like clusters. Species of Staphylococcus are anaerobic facultative organisms (aerobically and anaerobically capable of growth).

> Option D is incorrect. Staphylobacillus comprises a grape-like aggregate of rod-shaped bacteria or bacillus or bacilli clusters. Salmonella typhi, for instance. The shape of the rod can be shaped like a cigar or a straw.

Hence, the correct answer is option (B).

Note: Streptobacillus moniliformis was first isolated by the German microbiologist H. from a rat-bitten man in 1914. Schottmuller, who described it as Muris ratti Streptothrix. During the year 1916 in the United States. The causative cause of rat-bite fever was found to be S. moniliformis.