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Streptococcus pneumoniae is a bacterial pathogen that can cause pneumonia. Laboratory studies of various subtypes of this organism by The Rockefeller University scientists revealed that some of them produced colonies of different opacity (cloudiness). They found that compared with bacteria from opaque colonies, bacteria from more transparent colonies were found to grow more quickly and to adhere more efficiently to bronchial cells in culture. They also found that the bacteria from transparent colonies contained a phage strain called MM1-1998. Based on this information, which of the following statements are TRUE?

S. pneumoniae forming transparent colonies are lysogens.
S. pneumoniae bacteria containing MM1-1998 have a competitive advantage.
Providing that the culture conditions of the S. pneumoniae are unchanged, subsequent generations of this bacterium will also exhibit change in transparency and growth ability.

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Answer:

S. pneumoniae forming transparent colonies are lysogens.

S. pneumoniae bacteria containing MM1-1998 have a competitive advantage.

Providing that the culture conditions of the S. pneumoniae are unchanged, subsequent generations of this bacterium will also exhibit change in transparency and growth ability.

Explanation:

When S. pneumoniae form trasparent colonies are lysogens because they have a lysogenic cycle which is one of two cycles of viral reproduction (the lytic cycle being the other). Lysogeny is characterized by integration of the bacteriophage nucleic acid into the host bacterium's genome or formation of a circular replicon in the bacterial cytoplasm.

It has been discovered that adherence to inert surfaces and specifically to pharyngeal cells is associated with the MM1-1998 prophage, which may confer an advantage in colonization of the human nasopharynx. MM1-like phages are frequent and have been described in multiresistant, globally spread clones.

Bacteria can change—or mutate—making it possible to resist antibiotics. Public health experts call this antibiotic resistance. Many bacteria, including some Streptococcus pneumoniae (pneumococcus), have become resistant to one or more antibiotics. Resistance can lead to treatment failures.