Leucasin - Induced Cytoplasmic Membrane Damage in Staphylococcus aureus

Authors

  • S. Meghashr Department of Studies in Microbiology, University of Mysore, Mysore – 570 006, Karnataka, India
  • S. Gopal Department of Studies in Microbiology, University of Mysore, Mysore – 570 006, Karnataka, India

Keywords:

Leucasin, Mechanism of action, Staphylococcus aureu, Cytoplasmic membrane damage, Potassium loss

Abstract

Leucasin is one of the active antimicrobial principle of Leucas aspera. The effect of this compound and other antibacterial agents with known mechanisms of action upon the cytoplasmic membrane integrity of Staphylococcus aureus was investigated by comparing scanning electron microscopy (SEM) and potassium loss profiles from bacterial cell suspensions. The minimum inhibitory concentrations (MICs) of leucasin, novobiocin - the bacteriostatic antibiotic and penicillin G – the bactericidal antibiotic against S. aureus (ATCC 12600) were determined as 35 μg/ml, 55 ng/ml and 40 ng/ml respectively. The morphology of S. aureus was impaired, when treated with leucasin showing mucilaginous mass, which could lead to the impairment in cell division, as observed under SEM. When S. aureus were suspended in potassium free media containing 35 μg/ml leucasin, a 100 fold decrease in viability was observed after 12 h. Potassium loss assay revealed that S. aureus treated with 35 μg/ml leucasin lost 17% more potassium than untreated control populations whereas, cells treated with 40 ng/ml of penicillin G exhibited 9% increase in potassium loss and 55 ng/ml of novobiocin had no effect on potassium loss. This data may be attributed to either direct damage to the cytoplasmic membrane or indirect damage affected through autolysis/weakening of the cell wall and consequent osmotic lysis.

References

. Havsteen, B.H. The biochemistry and

medical significance of the

flavonoids. Pharmacol Ther. 2002;

: 67-202.

. Grange, J.M., and Davey, R.W.

Antibacterial properties of propolis

(bee glue). J R Soc Med. 1990; 83:

-160.

. Meghashri, S., Vijay Kumar, H., and

Gopal, S. Antioxidant properties of a

novel flavonoid from leaves of

Leucas aspera. Food Chem. 2010;

: 105-110.

. Sadhu, S.K., Okuyama, E., Fujimoto,

H., and Ishibashi, M. Separation of

Leucas aspera, a medicinal plant of

Bangladesh, guided by

prostaglandin inhibitory and

antioxidant activities. Chem Pharm

Bull. 2003; 51: 595-598.

. Kamaraj, C., Bagavan, A., Rahuman,

A.A., Zahir, A.A., Elango, G., and

Pandiyan, G. Larvicidal potential of

medicinal plant extracts against

Anopheles subpictus, Grassi and

Culex tritaeniorhynchus Giles

(Diptera: Culicidae). Parasitol Res.

; 104: 1163-1171.

. Kothari, S., Mishra, V., Bharat, S.,

and Tonpay, S.D. Antimicrobial

activity and phytochemical

screening of serial extracts from

leaves of Aegle marmelos (Linn.).

Acta Pol Pharm. 2011; 68: 687-692.

. Ikigai, H., Nakae, T., Hara, Y., and

Shimamura, T. Bactericidal

catechins damage the lipid bilayer.

Biochem Biophys Acta. 1993; 1147:

-136.

. Tsuchiya, H., and Iinuma, M.

Reduction of membrane fluidity by

antibacterial sophoraflavanone G

isolated from Sophora exigua.

Phytomedicine. 2000; 7: 161-165.

. Mirzoeva, O.K., Grishanin, R.N., and

Calder, P.C. Antimicrobial action of

propolis and some of its

components: the effects on growth

membrane potential and motility of

bacteria. Microbiol Res. 1997; 152:

-246.

. Lambert, R.J., Skandamis, P.N.,

Coote, P.J., and Nychas, G.J. A

study of the minimum inhibitory

concentration and mode of action of

oregano essential oil, thymol and

carvacrol. J Appl Microbiol. 2001;

: 453-462.

. Cushnie, T.P.T., Hamilton, V.E.S.,

and Lamb, A.J. Assessment of the

antibacterial activity of selected

flavonoids and consideration of

discrepancies between previous

reports. Microbiol Res. 2003; 158:

-289.

. Zameer, F., Shubha, G., Krohne, G.,

and Kreft, J. Development of

biofilms model for Listeria

monocytogenes. World J Microbiol

Biotechnol. 2010; 26: 1143-1147.

. Cushnie, T.P.T., and Lamb, A.J.

Antimicrobial activity of flavonoids.

Int J Anti Agents. 2005; 26: 343–

. Lewis, K. Programmed death in

bacteria. Microbiol Mol Biol Rev.

; 64: 503-514.

. Epstein, W. The roles and regulation

of potassium in bacteria. Prog

Nucleic Acid Res Mol Biol. 2003; 75:

-320.

. Block, J.H., Beale, J.M., and Wilson,

G. Textbook of organic medicinal

and pharmaceutical chemistry.

Lippincott Williams and Wilkins,

London. 2004.

. Plaper, A., Golob, M., Hafner, I.,

Oblak, M., Solmajer, T., and Jerala,

R. Characterization of quercetin

binding site on DNA gyrase.

Biochem Biophys Res Commun.

; 306: 530-536.

. Walsh, C. Molecular mechanisms

that confer antibacterial drug

resistance. Nature. 2000; 406: 775-

. Heidrich, C., Templin, M.F.,

Ursinus, A., Merdanovic, M., Berger,

J., Schwartz, H., de Pedro, M.A.,

and Holtje, J.V. Involvement of Nacetylmuramyl-L-alanine amidases

in cell separation and antibiotic

induced autolysis of E. coli. Mol

Microbiol. 2001; 41: 167-178.

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Published

30-06-2012

How to Cite

1.
S. Meghashr, S. Gopal. Leucasin - Induced Cytoplasmic Membrane Damage in Staphylococcus aureus. ijp [Internet]. 2012 Jun. 30 [cited 2024 Dec. 6];4(2):150-4. Available from: https://ijp.arjournals.org/index.php/ijp/article/view/156

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Short Communication