Aims: The surplus use of herbicide Dalapon® contains 2,2-dichloropropionic acid (2,2-DCP) poses great danger to human and ecosystem due to its toxicity. Hence, this study focused on the isolation and characterization of a dehalogenase producing bacteria from Sungai Skudai, Johor, capable of utilizing 2,2-DCP as a carbon source and in silico analysis of its putative dehalogenase. Methodology and results: Isolation of the target bacteria was done by using 2,2-DCP-enriched culture as the sole carbon source that allows a bacterium to grow in 20 mM of 2,2-DCP at 30 °C with the corresponding doubling time of 8.89 ± 0.03 h. The isolated bacterium was then designated as Klebsiella pneumoniae strain YZ based on biochemical tests and basic morphological examination. The full genome of K. pneumoniae strain KLPN_25 (accession number: RRE04903) which obtained from NCBI database was screened for the presence of dehalogenase gene, assuming both strains YZ and KLPN_25 were the same organisms. A putative dehalogenase gene was then identified as type II dehalogenase from the genome sequence of strain KLPN_25. The protein structure of the type II dehalogenase of KLPN_25 strain was then pairwise aligned with the crystal structure of L-2-haloacid dehalogenase (L-DEX) Pseudomonas sp. strain YL as the template, revealing the existence of conserved amino acids residues, uniquely known to participate in the dehalogenation mechanism. The finding thus implies that the amino acid residues of type II dehalogenase possibly shares similar catalytic functions with the L-DEX. Conclusion, significance and impact of the study In conclusion, this study confirmed the presence of new dehalogenase from the genus Klebsiella with potential to degrade 2,2-DCP from the river water. The structural information of type II dehalogenase provides insights for future work in designing haloacid dehalogenases.
Klebsiella pneumoniae--isolation & ; purification ; Computer Simulation ; Molecular Dynamics Simulation

No abstract available.
Aged ; Female ; Humans ; Klebsiella Infections/*diagnosis/microbiology ; Klebsiella pneumoniae/*enzymology/isolation & purification ; Pneumonia/*diagnosis/microbiology ; Turkey ; beta-Lactamases/*metabolism

Klebsiella pneumoniae ; enzymology ; isolation & purification ; Microbial Sensitivity Tests ; beta-Lactamases ; classification

Cross Infection ; microbiology ; Humans ; Klebsiella pneumoniae ; classification ; drug effects ; isolation & purification ; Microbial Sensitivity Tests

In recent years, there have been increasing reports of KPC-producing Klebsiella pneumoniae in Korea. The modified Hodge test can be used as a phenotypic screening test for class A carbapenamase (CAC)-producing clinical isolates; however, it does not distinguish between carbapenemase types. The confirmation of type of CAC is important to ensure optimal therapy and to prevent transmission. This study applied a novel multiplex PCR assay to detect and differentiate CAC genes in a single reaction. Four primer pairs were designed to amplify fragments encoding 4 CAC families (SME, IMI/NMC-A, KPC, and GES). The multiplex PCR detected all genes tested for 4 CAC families that could be differentiated by fragment size according to gene type. This multiplex PCR offers a simple and useful approach for detecting and distinguishing CAC genes in carbapenem-resistant strains that are metallo-beta-lactamase nonproducers.
Bacterial Proteins/*genetics/metabolism ; DNA Primers/metabolism ; Databases, Genetic ; Humans ; Klebsiella Infections/microbiology ; Klebsiella pneumoniae/genetics/isolation & purification/metabolism ; *Multiplex Polymerase Chain Reaction ; beta-Lactamases/*genetics/metabolism

OBJECTIVETo investigate and take a case study on a Klebsiella pneumoniae outbreak in a newborn intensive care unit (NICU).

METHODSUsing epidemiological investigation method to cultivate bacilli and detect the homology.

RESULTSKlebsiella pneumonia was detected in 4 NICU patients. Based on environmental sample analyses, four Klebsiella pneumonia strains were identified and confirmed to be highly homologous. The outbreak was effectively controlled after the strict implementation of hand hygiene practice and environment disinfection.

CONCLUSIONKlebsiella pneumonia outbreak in NICU may be caused by the route of hand transmission.

Cross Infection ; epidemiology ; microbiology ; Disease Outbreaks ; Female ; Humans ; Infant, Newborn ; Intensive Care Units, Neonatal ; Klebsiella Infections ; epidemiology ; microbiology ; Klebsiella pneumoniae ; genetics ; isolation & purification ; Male

Objective The aim of our study is to investigate the prevalence of Carbapenem-resistant Klebsiella pneumoniae (CRKP) and the genetic characteristics of the class 1 integron in CRKP on multi-drug resistance.Methods Clinical Klebsiella pneumoniae strains were collected from multiple departments of a hospital in central China. CRKP strains were identified among the isolates, and antibiotics susceptibility of CRKP strains was analyzed. The polymerase chain reaction (PCR) was adopted to amplify the class 1 integron variable area. The integron genetic structure was analyzed with enzyme digestion and DNA sequencing technology. The relation between class 1 integron and drug resistance was analyzed statistically.Results Totally 955 strains of Klebsiella pneumoniae were isolated from varied sites of the hospital, and 117(12.3%) of them were identified as CRKP, with a separation rate of 8.9% (26/292) in 2013, 11.3% (38/336) in 2014 and 16.2% (53/327) in 2015, which shows an increasing trend by year. 44.4% (52/117) of CRKP strains were separated from specimen of ICU, and 61.5% (72/117) were from sputum. Over 95% CRKP strains were resistant to ampicillin/sulbactam, aztreonam, imipenem, meropenem, ceftazidme, cefotaxime, cefepime,and piperacillin, while relatively low resistant rates were found in tigecycline (12.8%) and colistin (35.9%). The class 1 integron was detected in 77.8% (91/117) of CRKP strains. Class 1 integron of CRKP was significantly correlated with the antibiotic resistance to the tobramycin, gentamicin and amikacin (all P<0.01). The gene cassette analysis of variable area of class 1 integron showed that aadA2 accounts for 64.8% (59/91), aacA4-catB8-aadA1 23.1% (21/91), and aadA2-dfrA25 12.1% (11/91).Conclusions CRKP has an increasing trend in a clinical setting in China, and most of them were resistant to multiple antibiotics. Class 1 integron in CRKP has strong ability to capture the genes resistant to aminoglycosides antibiotics from environment, with the aadA2 gene as the most popular one.
Anti-Bacterial Agents ; pharmacology ; Carbapenems ; pharmacology ; Drug Resistance, Bacterial ; Integrons ; Klebsiella pneumoniae ; drug effects ; genetics ; isolation & purification

Anti-Bacterial Agents ; pharmacology ; Drug Resistance, Bacterial ; Humans ; Imipenem ; pharmacology ; Infant ; Klebsiella pneumoniae ; drug effects ; isolation & purification ; Ventilation ; methods

OBJECTIVETo compare the characteristics of urinary tract infection (UTI) between kidney transplant recipients and non-recipient patients.

METHODSForty-nine kidney transplant recipients with UTI (69 episodes) and 401 non-recipient patients with UTI (443 episodes) admitted in Nanfang Hospital from January 2003 to August 2014 were enrolled in the study. The characteristics of UTI were compared between two groups.

RESULTSIn both groups of UTI, female patients comprised a greater proportion (63.3% and 58.6%) and Escherichia coli was the most common pathogen isolated (37.7% and 34.1%). However, the infection rate of Klebsiella pneumonia in recipients was higher than that in non-recipients (11.6% vs 3.2%, P= 0.001), while the infection rate of Candida albicans was lower (1.5% vs 11.3%, P=0.008) than that in non-recipients. Recipients were likely to develop antibiotic resistance and with a higher recurrence rate than non-recipient patients (38.8% vs 16.7%, P<0.001). Compared to non-recipient UTI patients, the symptoms of urinary irritation in recipient UTI patients were more common. There was higher percentage of neutrophil granulocyte (72.65% ± 1.90% vs 68.59% ± 0.73%, P=0.048), lower proportion of lymphocytes (17.73% ± 1.27% vs 21.28% ± 0.61%, P=0.037), and less platelets [(187.64 ± 10.84) × 10(9)/L vs (240.76 ± 5.26) × 10(9)/L, P<0.01] in recipients than in non-recipient UTI patients.

CONCLUSIONThese results indicate that the characteristics of UTI in kidney transplantation recipients and non-recipients patients are different.

Candida albicans ; isolation & purification ; Escherichia coli ; isolation & purification ; Female ; Humans ; Kidney Transplantation ; Klebsiella pneumoniae ; isolation & purification ; Male ; Transplant Recipients ; Urinary Tract Infections ; epidemiology ; pathology

INTRODUCTIONAt the time of the study, 3 plasmid-borne qnr determinants (qnrA, qnrB and qnrS) and 1 plasmid-borne aminoglycoside-modifying enzyme determinant that confers quinolone resistance (aac(6')-Ib-cr) had been described in the literature.

MATERIALS AND METHODSWe studied the prevalence of the 3 qnr determinants in a total of 117 nalidixic acid-resistant urinary isolates of Klebsiella pneumoniae (61 isolates) and Escherichia coli (56 isolates) using multiplex polymerase chain reaction (PCR). Further, a subset of the original strains (comprising 14 E. coli and 38 K. pneumoniae) showing reduced susceptibility to the aminoglycosides underwent PCR for aac(6')-Ib, followed by restriction digestion with BtsCI to detect the variant aac(6')-Ib-cr.

RESULTSTwenty-eight of 61 (45.9%) Klebsiella isolates were found to possess at least 1 qnr determinant. Only 1/56 (1.8%) E. coli isolates were found to possess a qnr determinant. Two of the Klebsiella isolates possessed 2 qnr determinants each (qnrB and qnrS). The predominant determinant was qnrB (19 isolates). There were 11 isolates harbouring qnrS, and only 1 with qnrA. 1/14 (7.1%) E. coli and 35/38 K. pneumoniae (92.1%) were found to possess aac(6')-Ib-cr. There was pairwise association between each of qnr, aac(6')-Ib-cr and the presence of an extended-spectrum beta-lactamase.

CONCLUSIONSA high prevalence of plasmid-mediated quinolone resistance determinants [i.e., qnrS, qnrB and aac(6')-Ib-cr] was found in quinolone-resistant K. pneumoniae isolated in a large hospital in Singapore.

Drug Resistance, Bacterial ; Escherichia coli ; drug effects ; isolation & purification ; Hospitals ; Humans ; Klebsiella pneumoniae ; drug effects ; isolation & purification ; Molecular Sequence Data ; Quinolones ; pharmacology ; R Factors ; Singapore ; Urine ; microbiology