Biofilms from Klebsiella pneumoniae: Matrix Polysaccharide Structure and Interactions with Antimicrobial Peptides.
Biofilm matrices of two Klebsiella pneumoniae clinical isolates, KpTs101 and KpTs113, were investigated for their polysaccharide composition and protective effects against antimicrobial peptides. Both strains were good biofilm producers, with KpTs113 forming flocs with very low adhesive properties to supports. Matrix exopolysaccharides were isolated and their monosaccharide composition and glycosidic linkage types were defined. KpTs101 polysaccharide is neutral and composed only of galactose, in both pyranose and furanose ring configurations. Conversely, KpTs113 polysaccharide is anionic due to glucuronic acid units, and also contains glucose and mannose residues. The susceptibility of the two strains to two bovine cathelicidin antimicrobial peptides, BMAP-27 and Bac7(1-35), was assessed using both planktonic cultures and biofilms. Biofilm matrices exerted a relevant protection against both antimicrobials, which act with quite different mechanisms. Similar protection was also detected when antimicrobial peptides were tested against planktonic bacteria in the presence of the polysaccharides extracted from KpTs101 and KpTs113 biofilms, suggesting sequestering adduct formation with antimicrobials. Circular dichroism experiments on BMAP-27 in the presence of increasing amounts of either polysaccharide confirmed their ability to interact with the peptide and induce an α-helical conformation.
Department of Life Sciences, University of Trieste, Via L. Giorgieri 1, Trieste I-34127, Italy. mbenincasa@units.it.
Monica
M
Benincasa
Department of Life Sciences, University of Trieste, Via L. Giorgieri 1, Trieste I-34127, Italy. clagatolla@units.it.
Cristina
C
Lagatolla
Department of Life Sciences, University of Trieste, Via L. Giorgieri 1, Trieste I-34127, Italy. ldolzani@units.it.
Lucilla
L
Dolzani
Department of Life Sciences, University of Trieste, Via L. Giorgieri 1, Trieste I-34127, Italy. annalisa.milan@phd.units.it.
Annalisa
A
Milan
Department of Life Sciences, University of Trieste, Via L. Giorgieri 1, Trieste I-34127, Italy. pacorsab@units.it.
Sabrina
S
Pacor
Department of Life Sciences, University of Trieste, Via L. Giorgieri 1, Trieste I-34127, Italy. gianliut@gmail.com.
Gianfranco
G
Liut
Department of Life Sciences, University of Trieste, Via L. Giorgieri 1, Trieste I-34127, Italy. atossi@units.it.
Alessandro
A
Tossi
Department of Life Sciences, University of Trieste, Via L. Giorgieri 1, Trieste I-34127, Italy. pcescutti@units.it.
Paola
P
Cescutti
Department of Life Sciences, University of Trieste, Via L. Giorgieri 1, Trieste I-34127, Italy. rizzor@units.it.
Roberto
R
Rizzo
Klebsiella pneumoniae; antimicrobial peptides; biofilm matrix; matrix polysaccharides
Cell Mol Life Sci. 2011 Jul;68(13):2317-30
21594684
Peptides. 2004 Dec;25(12):2055-61
15572192
Science. 1999 May 21;284(5418):1318-22
10334980
J Bacteriol. 1991 Feb;173(4):1420-31
1704883
Mol Microbiol. 2009 Jun;72(5):1137-46
19400793
J Pept Sci. 2012 Feb;18(2):105-13
22083804
FEMS Immunol Med Microbiol. 2011 Oct;63(1):10-5
21595755
J Pept Sci. 2009 Sep;15(9):576-82
19472166
Biochem J. 2014 Jan 15;457(2):263-75
24117320
Nature. 2002 Jan 24;415(6870):389-95
11807545
Carbohydr Res. 2016 Jul 22;430:29-35
27182661
J Biol Chem. 1996 Nov 8;271(45):28375-81
8910461
Biochemistry. 2009 Nov 24;48(46):10905-17
19845398
Biochemistry. 1974 Jul 30;13(16):3350-9
4366945
Biochim Biophys Acta. 2006 Nov;1760(11):1732-40
17059867
Curr Protoc Microbiol. 2005 Jul;Chapter 1:Unit 1B.1
18770545
J Biochem. 1995 Mar;117(3):560-5
7629022
Antimicrob Agents Chemother. 2009 Aug;53(8):3501-4
19470515
J Clin Microbiol. 2004 May;42(5):1915-22
15131149
Microbiology. 2000 Oct;146 ( Pt 10):2395-407
11021916
Probiotics Antimicrob Proteins. 2010 Mar;2(1):12-20
26780897
Clin Microbiol Rev. 1998 Oct;11(4):589-603
9767057
Carbohydr Res. 1984 Apr 2;127(1):59-73
6713442
BMC Microbiol. 2012 Jul 23;12:145
22823964
J Med Chem. 2015 Feb 12;58(3):1195-204
25525837
Infect Immun. 2004 Dec;72(12):7107-14
15557634
Pathogens. 2014 Sep 05;3(3):743-58
25438022
Annu Rev Microbiol. 1995;49:711-45
8561477
Philos Trans R Soc Lond B Biol Sci. 2016 May 26;371(1695):null
27160595
Peptides. 2005 Jul;26(7):1127-32
15949630
Antimicrob Agents Chemother. 2015 Jul;59(7):3906-12
25896694