Genetic and phenotypic characterization of klebsiella pneumoniae isolated from Matang mangrove estuary Malaysia / Anis Barati
The genus Klebsiella is ubiquitous in nature. The environmental sources of this bacterium include soil, surface waters, plants, sewage, industrial effluents and mammalian gastrointestinal tract. K. pneumoniae is an opportunistic Gram-negative bacterium and is an emergent multidrug resistant strai...
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| Format: | Thesis |
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2014
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| Online Access: | http://studentsrepo.um.edu.my/7235/ http://studentsrepo.um.edu.my/7235/1/Anis_Barati_Thesis.pdf |
| _version_ | 1848773341823893504 |
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| author | Anis, Barati |
| author_facet | Anis, Barati |
| author_sort | Anis, Barati |
| building | UM Research Repository |
| collection | Online Access |
| description | The genus Klebsiella is ubiquitous in nature. The environmental sources of this
bacterium include soil, surface waters, plants, sewage, industrial effluents and
mammalian gastrointestinal tract. K. pneumoniae is an opportunistic Gram-negative
bacterium and is an emergent multidrug resistant strain with potential virulence to
human. In this study, phenotypic and genotypic methods were used to screen for
potentially pathogenic K. pneumoniae isolated from Matang mangrove estuary. Out of
162 Enterobacteriaceae isolates collected from Matang mangrove estuaries, E. coli
(n=47), Enterobacter spp. (n=42), Klebsiella spp. (n=36), Serratia spp. (n=18) and
others (n=19) were identified by biochemical assay. Subsequently, out of the 78
presumptive isolates of Klebsiella spp. and Enterobacter spp., 55 were confirmed as K.
pneumoniae by PCR targeting the malate dehydrogenase gene. The confirmed isolates
of K. pneumoniae were analyzed for antibiotics susceptibility, capsule production,
biofilm formation, exopolysaccharide production and morphotype on Congo red agar
plate. Also, the isolates were subjected for virulotyping and genetic fingerprinting with
Repetitive Element Palindromic PCR (REP-PCR). Out of the 8 virulence genes, K1, K2
(capsular antigen), wabG, magA (biosynthesis of outer core lipopolysaccharide antigen),
rmpA (mucoid phenotype regulator), kfu (iron up-taking system), fimH (fimberia
adhesion) and ugE (biosynthesis of capsule and smooth lipopolysaccharide) tested, only
fimH, ugE and wabG were detected with high prevalence (95%) among K. pneumoniae
isolates. In general, the isolates could be grouped into four major clusters based on the
REP-PCR fingerprints, in which isolates with certain similar phenotypes were grouped
together. Antibiotics susceptibility test showed that majority of K. pneumoniae isolates
(87.3%) were sensitive to the all the antibiotics tested, except for Ampicillin. However,
12.7% of the isolates were found to be multi drug resistant to more than 2 classes of
antibiotics. These multi drug resistant isolates were mainly isolated from one station located at river mouth with high salinity (18.03ppt). The waterborne K. pneumoniae
from Matang mangrove estuary demonstrated low prevalence (5%) of strong biofilm
forming ability. In conclusion, due to presence of some virulence factors like,
hypermucoid phenotype, biofilm formation ability, and capsular production and the
presence of virulence gene (fimH, wabG, ugE) in these waterborne K. pneumoniae,
these localities pose a risk of infection to the villagers. |
| first_indexed | 2025-11-14T13:40:52Z |
| format | Thesis |
| id | um-7235 |
| institution | University Malaya |
| institution_category | Local University |
| last_indexed | 2025-11-14T13:40:52Z |
| publishDate | 2014 |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | um-72352017-03-16T04:09:19Z Genetic and phenotypic characterization of klebsiella pneumoniae isolated from Matang mangrove estuary Malaysia / Anis Barati Anis, Barati Q Science (General) QR Microbiology The genus Klebsiella is ubiquitous in nature. The environmental sources of this bacterium include soil, surface waters, plants, sewage, industrial effluents and mammalian gastrointestinal tract. K. pneumoniae is an opportunistic Gram-negative bacterium and is an emergent multidrug resistant strain with potential virulence to human. In this study, phenotypic and genotypic methods were used to screen for potentially pathogenic K. pneumoniae isolated from Matang mangrove estuary. Out of 162 Enterobacteriaceae isolates collected from Matang mangrove estuaries, E. coli (n=47), Enterobacter spp. (n=42), Klebsiella spp. (n=36), Serratia spp. (n=18) and others (n=19) were identified by biochemical assay. Subsequently, out of the 78 presumptive isolates of Klebsiella spp. and Enterobacter spp., 55 were confirmed as K. pneumoniae by PCR targeting the malate dehydrogenase gene. The confirmed isolates of K. pneumoniae were analyzed for antibiotics susceptibility, capsule production, biofilm formation, exopolysaccharide production and morphotype on Congo red agar plate. Also, the isolates were subjected for virulotyping and genetic fingerprinting with Repetitive Element Palindromic PCR (REP-PCR). Out of the 8 virulence genes, K1, K2 (capsular antigen), wabG, magA (biosynthesis of outer core lipopolysaccharide antigen), rmpA (mucoid phenotype regulator), kfu (iron up-taking system), fimH (fimberia adhesion) and ugE (biosynthesis of capsule and smooth lipopolysaccharide) tested, only fimH, ugE and wabG were detected with high prevalence (95%) among K. pneumoniae isolates. In general, the isolates could be grouped into four major clusters based on the REP-PCR fingerprints, in which isolates with certain similar phenotypes were grouped together. Antibiotics susceptibility test showed that majority of K. pneumoniae isolates (87.3%) were sensitive to the all the antibiotics tested, except for Ampicillin. However, 12.7% of the isolates were found to be multi drug resistant to more than 2 classes of antibiotics. These multi drug resistant isolates were mainly isolated from one station located at river mouth with high salinity (18.03ppt). The waterborne K. pneumoniae from Matang mangrove estuary demonstrated low prevalence (5%) of strong biofilm forming ability. In conclusion, due to presence of some virulence factors like, hypermucoid phenotype, biofilm formation ability, and capsular production and the presence of virulence gene (fimH, wabG, ugE) in these waterborne K. pneumoniae, these localities pose a risk of infection to the villagers. 2014 Thesis NonPeerReviewed application/pdf http://studentsrepo.um.edu.my/7235/1/Anis_Barati_Thesis.pdf Anis, Barati (2014) Genetic and phenotypic characterization of klebsiella pneumoniae isolated from Matang mangrove estuary Malaysia / Anis Barati. Masters thesis, University of Malaya. http://studentsrepo.um.edu.my/7235/ |
| spellingShingle | Q Science (General) QR Microbiology Anis, Barati Genetic and phenotypic characterization of klebsiella pneumoniae isolated from Matang mangrove estuary Malaysia / Anis Barati |
| title | Genetic and phenotypic characterization of klebsiella pneumoniae isolated from Matang mangrove estuary Malaysia / Anis Barati |
| title_full | Genetic and phenotypic characterization of klebsiella pneumoniae isolated from Matang mangrove estuary Malaysia / Anis Barati |
| title_fullStr | Genetic and phenotypic characterization of klebsiella pneumoniae isolated from Matang mangrove estuary Malaysia / Anis Barati |
| title_full_unstemmed | Genetic and phenotypic characterization of klebsiella pneumoniae isolated from Matang mangrove estuary Malaysia / Anis Barati |
| title_short | Genetic and phenotypic characterization of klebsiella pneumoniae isolated from Matang mangrove estuary Malaysia / Anis Barati |
| title_sort | genetic and phenotypic characterization of klebsiella pneumoniae isolated from matang mangrove estuary malaysia / anis barati |
| topic | Q Science (General) QR Microbiology |
| url | http://studentsrepo.um.edu.my/7235/ http://studentsrepo.um.edu.my/7235/1/Anis_Barati_Thesis.pdf |