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N-acyl homoserine lactone production by Klebsiella pneumoniae isolated from human tongue surface.

Yin WF, Purmal K, Chin S, Chan XY, Koh CL, Sam CK, Chan KG - Sensors (Basel) (2012)

Bottom Line: Here, we report the isolation of two AHL-producing Klebsiella pneumoniae strains from the posterior dorsal surface of the tongue of a healthy individual.Spent culture supernatant extracts from K. pneumoniae activated the biosensors Agrobacterium tumefaciens NTL4(pZLR4) and Escherichia coli [pSB401], suggesting the presence of both long and short chain AHLs.High resolution mass spectrometry analyses of these extracts confirmed that both K. pneumoniae isolates produced N-octanoylhomoserine lactone and N-3-dodecanoyl-L-homoserine lactone.

View Article: PubMed Central - PubMed

Affiliation: Division of Genetics and Molecular Biology, Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia. yinwaifong@yahoo.com

ABSTRACT
Bacteria communicate by producing quorum sensing molecules called autoinducers, which include autoinducer-1, an N-hexanoyl homoserine lactone (AHL), and autoinducer-2. Bacteria present in the human oral cavity have been shown to produce autoinducer-2, but not AHL. Here, we report the isolation of two AHL-producing Klebsiella pneumoniae strains from the posterior dorsal surface of the tongue of a healthy individual. Spent culture supernatant extracts from K. pneumoniae activated the biosensors Agrobacterium tumefaciens NTL4(pZLR4) and Escherichia coli [pSB401], suggesting the presence of both long and short chain AHLs. High resolution mass spectrometry analyses of these extracts confirmed that both K. pneumoniae isolates produced N-octanoylhomoserine lactone and N-3-dodecanoyl-L-homoserine lactone. To the best of our knowledge, this is the first report of the isolation of K. pneumoniae from the posterior dorsal surface of the human tongue and the production of these AHLs by this bacterium.

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16S rDNA-based phylogenetic tree showing the phylogenetic positions of oral bacterial isolates T2-1-1 and T2-1-2. A total of 912 unambiguously aligned nucleotides were analysed using MEGA 4. The percentages of replicate trees in which the associated taxa clustered together in the bootstrap test are shown next to the branches. The tree is drawn to scale, with branch lengths in the same units as those of the evolutionary distances used to infer the phylogenetic tree. The bar at the bottom represents evolutionary distance as 0.002 change per nucleotide position. GenBank accession numbers are given in parentheses: K. oxytoca (AB476819), K. pneumoniae subsp. pneumoniae (CP000647), K. pneumoniae strain K30 (EU661377), and K. pneumoniae 342 (CP000964).
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f2-sensors-12-03472: 16S rDNA-based phylogenetic tree showing the phylogenetic positions of oral bacterial isolates T2-1-1 and T2-1-2. A total of 912 unambiguously aligned nucleotides were analysed using MEGA 4. The percentages of replicate trees in which the associated taxa clustered together in the bootstrap test are shown next to the branches. The tree is drawn to scale, with branch lengths in the same units as those of the evolutionary distances used to infer the phylogenetic tree. The bar at the bottom represents evolutionary distance as 0.002 change per nucleotide position. GenBank accession numbers are given in parentheses: K. oxytoca (AB476819), K. pneumoniae subsp. pneumoniae (CP000647), K. pneumoniae strain K30 (EU661377), and K. pneumoniae 342 (CP000964).

Mentions: The growth medium became turbid within 48 hours after inoculation with the tongue surface debris suggesting bacterial growth. At the end of the enrichment process, cell suspensions were serially diluted and streaked on LB agar. Pure colonies with distinctive morphologies were obtained after several successive streaks. Isolates T2-1-1 and T2-1-2 from the tongue surface debris specimen were selected for further analysis. The partial 16S rDNA sequences of T2-1-1 and T2-1-2, each comprising 1,532 nucleotides, were deposited in the GenBank under accession numbers HQ907955 (T2-1-1) and HQ907956 (T2-1-2). Web-based search and phylogenetic analysis showed that both T2-1-1 and T2-1-2 were K. pneumoniae (Figure 2).


N-acyl homoserine lactone production by Klebsiella pneumoniae isolated from human tongue surface.

Yin WF, Purmal K, Chin S, Chan XY, Koh CL, Sam CK, Chan KG - Sensors (Basel) (2012)

16S rDNA-based phylogenetic tree showing the phylogenetic positions of oral bacterial isolates T2-1-1 and T2-1-2. A total of 912 unambiguously aligned nucleotides were analysed using MEGA 4. The percentages of replicate trees in which the associated taxa clustered together in the bootstrap test are shown next to the branches. The tree is drawn to scale, with branch lengths in the same units as those of the evolutionary distances used to infer the phylogenetic tree. The bar at the bottom represents evolutionary distance as 0.002 change per nucleotide position. GenBank accession numbers are given in parentheses: K. oxytoca (AB476819), K. pneumoniae subsp. pneumoniae (CP000647), K. pneumoniae strain K30 (EU661377), and K. pneumoniae 342 (CP000964).
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3376583&req=5

f2-sensors-12-03472: 16S rDNA-based phylogenetic tree showing the phylogenetic positions of oral bacterial isolates T2-1-1 and T2-1-2. A total of 912 unambiguously aligned nucleotides were analysed using MEGA 4. The percentages of replicate trees in which the associated taxa clustered together in the bootstrap test are shown next to the branches. The tree is drawn to scale, with branch lengths in the same units as those of the evolutionary distances used to infer the phylogenetic tree. The bar at the bottom represents evolutionary distance as 0.002 change per nucleotide position. GenBank accession numbers are given in parentheses: K. oxytoca (AB476819), K. pneumoniae subsp. pneumoniae (CP000647), K. pneumoniae strain K30 (EU661377), and K. pneumoniae 342 (CP000964).
Mentions: The growth medium became turbid within 48 hours after inoculation with the tongue surface debris suggesting bacterial growth. At the end of the enrichment process, cell suspensions were serially diluted and streaked on LB agar. Pure colonies with distinctive morphologies were obtained after several successive streaks. Isolates T2-1-1 and T2-1-2 from the tongue surface debris specimen were selected for further analysis. The partial 16S rDNA sequences of T2-1-1 and T2-1-2, each comprising 1,532 nucleotides, were deposited in the GenBank under accession numbers HQ907955 (T2-1-1) and HQ907956 (T2-1-2). Web-based search and phylogenetic analysis showed that both T2-1-1 and T2-1-2 were K. pneumoniae (Figure 2).

Bottom Line: Here, we report the isolation of two AHL-producing Klebsiella pneumoniae strains from the posterior dorsal surface of the tongue of a healthy individual.Spent culture supernatant extracts from K. pneumoniae activated the biosensors Agrobacterium tumefaciens NTL4(pZLR4) and Escherichia coli [pSB401], suggesting the presence of both long and short chain AHLs.High resolution mass spectrometry analyses of these extracts confirmed that both K. pneumoniae isolates produced N-octanoylhomoserine lactone and N-3-dodecanoyl-L-homoserine lactone.

View Article: PubMed Central - PubMed

Affiliation: Division of Genetics and Molecular Biology, Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia. yinwaifong@yahoo.com

ABSTRACT
Bacteria communicate by producing quorum sensing molecules called autoinducers, which include autoinducer-1, an N-hexanoyl homoserine lactone (AHL), and autoinducer-2. Bacteria present in the human oral cavity have been shown to produce autoinducer-2, but not AHL. Here, we report the isolation of two AHL-producing Klebsiella pneumoniae strains from the posterior dorsal surface of the tongue of a healthy individual. Spent culture supernatant extracts from K. pneumoniae activated the biosensors Agrobacterium tumefaciens NTL4(pZLR4) and Escherichia coli [pSB401], suggesting the presence of both long and short chain AHLs. High resolution mass spectrometry analyses of these extracts confirmed that both K. pneumoniae isolates produced N-octanoylhomoserine lactone and N-3-dodecanoyl-L-homoserine lactone. To the best of our knowledge, this is the first report of the isolation of K. pneumoniae from the posterior dorsal surface of the human tongue and the production of these AHLs by this bacterium.

Show MeSH
Related in: MedlinePlus