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Generation of a Gene-disrupted Streptococcus mutans Strain Without Gene Cloning
Published on: October 23, 2017
Mutacin II, a bactericidal antibiotic from Streptococcus mutans
M L Chikindas1, J Novák, A J Driessen
1Unilever Dental Research, United Kingdom.
Antimicrobial Agents and Chemotherapy
|December 1, 1995
Summary
Mutacin II, an antibiotic from Streptococcus mutans, kills bacteria by disrupting energy production. This novel mechanism inhibits essential enzyme functions, unlike other known antibiotic classes.
Area of Science:
- Microbiology
- Biochemistry
- Pharmacology
Background:
- Mutacin II is an antibiotic produced by group II Streptococcus mutans.
- It inhibits the growth of other streptococci and gram-positive microorganisms.
- The mechanism of action for Mutacin II was previously unknown.
Purpose of the Study:
- To elucidate the mechanism of action of Mutacin II.
- To characterize the effects of Mutacin II on bacterial cells.
- To classify Mutacin II in relation to known antibiotic mechanisms.
Main Methods:
- Assessed the bactericidal activity of Mutacin II.
- Measured transmembrane electrical potential (delta psi) and pH gradient (delta pH).
- Investigated the effect on amino acid transport and intracellular ATP levels.
Main Results:
- Mutacin II exhibits bactericidal activity.
- It causes transient depolarization of delta psi and delta pH.
- Mutacin II inhibits amino acid transport and rapidly depletes intracellular ATP, preventing its generation.
Conclusions:
- Mutacin II does not act as a pore-forming (Type A) or phospholipase/peptidoglycan synthesis inhibitor (Type B) antibiotic.
- Mutacin II functions by inhibiting essential enzyme activities involved in metabolic energy generation.
- This represents a novel, unclassified mechanism of antibiotic action.
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