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Analysis of the Lipid Composition of Mycobacteria by Thin Layer Chromatography
Published on: April 16, 2021
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Polysaccharide length affects mycobacterial cell shape and antibiotic susceptibility
Alexander M Justen1,2, Heather L Hodges3, Lili M Kim2
1Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge, MA 02139, USA.
Science Advances
|September 17, 2020
Summary
Bacterial polysaccharide length impacts cell function and antibiotic effectiveness. Shortening mycobacterial galactan affects cell physiology and increases susceptibility to certain antibiotics.
Area of Science:
- Microbiology
- Cell Biology
- Biochemistry
Background:
- Bacteria regulate polysaccharide chain length, influencing cell viability, physiology, virulence, and immune evasion.
- Polysaccharide chain length is known to affect immunomodulation, but its impact on bacterial physiology and antibiotic susceptibility remains unclear.
Purpose of the Study:
- To investigate the physiological consequences of truncating the mycobacterial galactan, an essential linear polysaccharide.
- To determine the effect of galactan chain length on bacterial morphology, fitness, and antibiotic susceptibility.
Main Methods:
- Systematic variation of mycobacterial galactan chain length.
- Analysis of cell morphology and fitness.
- Assessment of antibiotic susceptibility to hydrophobic antibiotics.
Main Results:
- Reducing galactan chain length by approximately half compromises bacterial fitness and alters cell morphology.
- Truncated galactan increases the potency of hydrophobic antibiotics.
- Galactan chain length was found to directly determine periplasm size in mycobacteria.
Conclusions:
- Glycan chain length can directly influence bacterial cellular physiology and antibiotic activity.
- Mycobacterial glycans, rather than proteins, play a crucial role in regulating periplasm size.
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