scholarly journals The Surface Protein Fructose-1, 6 Bisphosphate Aldolase of Klebsiella pneumoniae Serotype K1: Role of Interaction with Neutrophils

Pathogens ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 1009
Author(s):  
Chen-Hsiang Lee ◽  
Seng-Kee Chuah ◽  
Chia-Chi Chang ◽  
Fang-Ju Chen

Hypermucoviscosity phenotypic Klebsiella pneumoniae (HV-Kp) serotype K1 is the predominant pathogen of a pyogenic liver abscess, an emerging infectious disease that often complicates septic metastatic syndrome in diabetic patients with poor sugar control. HV-Kpisolates were more resistant to neutrophil phagocytosis than non-HV-Kpisolates because of different pathogen-associated molecular patterns. The protein expression of HV-Kp after interaction with neutrophils is unclear. We studied KP-M1 (HV phenotype; serotype K1), DT-X (an acapsularmutant strain of KP-M1), and E. coli (ATCC 25922) with the model of Kp-infected neutrophils, using a comparative proteomic approach. One the identified protein, namely fructose-1, 6-bisphosphate aldolase (FBA), was found to be distributed in the KP-M1 after infecting neutrophils. Cell fractionation experiments showed that FBA is localized both to the cytoplasm and the outer membrane. Flow cytometry demonstrated that outer membrane-localized FBA was surface-accessible to FBA-specific antibody. The fba gene expression was enhanced in high glucose concentrations, which leads to increasing bacterial resistance to neutrophils phagocytosis and killing. The KP-M1 after FBA inhibitors and FBA-specific antibody treatment showed a significant reduction in bacterial resistance to neutrophils phagocytosis and killing, respectively, compared to KP-M1 without treatment. FBA is a highly conserved surface-exposed protein that is required for optimal interaction of HV-Kp to neutrophils.

2021 ◽  
Vol 12 ◽  
Author(s):  
Jie Zhu ◽  
Tao Wang ◽  
Liang Chen ◽  
Hong Du

Hypervirulent Klebsiella pneumoniae (hvKP) has spread globally since first described in the Asian Pacific Rim. It is an invasive variant that differs from the classical K. pneumoniae (cKP), with hypermucoviscosity and hypervirulence, causing community-acquired infections, including pyogenic liver abscess, pneumonia, meningitis, and endophthalmitis. It utilizes a battery of virulence factors for survival and pathogenesis, such as capsule, siderophores, lipopolysaccharide, fimbriae, outer membrane proteins, and type 6 secretion system, of which the former two are dominant. This review summarizes these hvKP-associated virulence factors in order to understand its molecular pathogenesis and shed light on new strategies to improve the prevention, diagnosis, and treatment of hvKP-causing infection.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Chien-Hsiang Tai ◽  
Chien-Ning Hsu ◽  
Shih-Cheng Yang ◽  
Cheng-Kun Wu ◽  
Chih-Ming Liang ◽  
...  

AbstractIn this study, we aimed to investigate the impact of aspirin on the risk of pyogenic liver abscess caused by Klebsiella pneumoniae (KP-PLA) and invasive KP-PLA syndrome (IKPS) in diabetic patients. Diabetic patients who were propensity-score matched were retrospectively included from hospital-based database. Kaplan–Meier approach with a log-rank test was used to compare the cumulative incidences of KP-PLA including IKPS between aspirin users and non-users. Totally, 63,500 patients were analyzed after propensity-score matching (1:1). Compared with that of non-users, the incidence of KP-PLA was significantly reduced in aspirin users (0.31% vs. 0.50%, p < 0.01), but not for that of IKPS (0.02% vs. 0.03%, p = 0.29). Patients taking aspirin for ≥ 90 days had a significantly lower risk for KP-PLA (hazard ratio, 0.67; 95%CI, 0.50–0.90). Females, taking clopidogrel or metformin for ≥ 90 days, and taking H2-blockers or proton pump inhibitors (PPIs) for ≥ 5 days were also associated with a lower risk of KP-PLA. However, cholangitis and a glycated hemoglobin ≥ 8.5% were associated with an increased risk of KP-PLA.


Author(s):  
Tingting Le ◽  
Ling Wang ◽  
Chaoying Zeng ◽  
Leiwen Fu ◽  
Zhihua Liu ◽  
...  

Abstract Background Klebsiella pneumoniae (K. pneumoniae) is a common pathogen associated with hospital and community-onset infections. This study aimed to compare the clinical and microbiological characteristics of nosocomial, healthcare-associated (HCA), and community-acquired (CA) K. pneumoniae infections. Methods Clinical data were extracted from electronic medical records and analyzed retrospectively. Antimicrobial susceptibility and extended-spectrum beta-lactamase (ESBL) production were determined for all identified strains. Carbapenemase and ESBL genes were amplified by PCR. Genotyping of carbapenem-resistant K. pneumoniae (CRKP) and ESBL-producing strains was performed by pulsed-field gel electrophoresis (PFGE). Results Of 379 K. pneumoniae infections, 98 (25.9%) were nosocomial, 195 (51.5%) were healthcare-associated, and 86 (22.6%) were community-acquired. Hematological malignancy (OR = 4.467), and hypertension (OR = 2.08) and cerebral vascular disease (OR = 2.486) were associated with nosocomial and HCA infections respectively, when compared to CA infections. Overall, the incidence of antimicrobial resistance for the majority of agents tested was similar between nosocomial and HCA infections (P > 0.05) and both groups had a higher incidence than CA infections (P < 0.05). Moreover, 95.1% (78/82) of CRKP strains were isolated from the nosocomial and HCA groups. The blaKPC was the most prevalent carbapenemase gene among CRKP strains (80.5%, 66/82). ESBL-producing strains were prevalent among nosocomial (40.8%), HCA (35.9%) and CA groups (24.4%). The blaCTX-M-9-group and blaCTX-M-1-group genes were predominant in nosocomial (65.0%) and CA strains (66.7%), respectively. PFGE results showed ESBL-producing and CRKP strains were genetically diverse. Identical PFGE profiles were observed among HCA and nosocomial strains. Conclusions Nosocomial and HCA K. pneumoniae infections presented similar clinical features and antimicrobial resistance, and both two types of infections were different to CA infections. CRKP and ESBL-producing strains were disseminated mainly in HCA and nosocomial groups, and showed a clonal diversity. The cross transmission of CRKP was existed among HCA and nosocomial patients. This finding suggests that similar empirical therapy should be considered for patients with nosocomial and HCA K. pneumoniae infections and bacterial resistance surveillance of these infections is necessary.


Author(s):  
Hussam Mousa ◽  
Ghada Salameh Mohammed Al-Bluwi ◽  
Zainab Fathi Mohammed Al Drini ◽  
Huda Imam Gasmelseed ◽  
Jamal Aldeen Alkoteesh ◽  
...  

Abstract Background There is a dearth of information on liver abscesses in the United Arab Emirates. Herein, we describe the clinical features of liver abscesses and determine their incidence rates and clinical outcomes. Methods We retrospectively reviewed the clinical charts of adult patients with a primary diagnosis of liver abscess at a major hospital over a 7-year period. Results Amongst 45 patients, 82.2% (37/45) had a pyogenic liver abscess (PLA) and 17.8% (8/45) had amoebic liver abscesses (ALA). Overall, patients were young (median age 42 years, IQR 35–52), mostly males (77.8%, 35/45) from the Indian subcontinent (55.6%, 25/45), presented with fever (88.9%, 40/45) and abdominal pain (88.9%, 40/45), and had a solitary abscess on imaging (71.1% (32/45). Crude annual incidence rates were 35.9/100,000 hospital admissions (95% CI 26.2–48.0) and 5.9/100,000 inhabitants (95% CI 4.3–7.9). All ALA patients were from the Indian subcontinent (100%, 8/8). Klebsiella pneumoniae was the most frequent pathogen in PLA (43.2% [16/37], 95% CI 27.1–60.5%). The hospital stay was shorter in ALA (7.5 days, IQR 7–8.5) than in PLA (14 days, IQR 9–17). No deaths were recorded within 30 days of hospitalisation. Conclusions ALA was exclusively seen in migrants from the Indian subcontinent, suggesting importation. Further research to characterise K. pneumoniae isolates and assess potential risk factors is needed.


2021 ◽  
Vol 9 (2) ◽  
pp. 335
Author(s):  
Novaria Sari Dewi Panjaitan ◽  
Yu-Tze Horng ◽  
Chih-Ching Chien ◽  
Hung-Chi Yang ◽  
Ren-In You ◽  
...  

Capsular polysaccharide (CPS) is a crucial virulence factor for Klebsiella pneumoniae infection. We demonstrated an association of CPS production with two phosphoenolpyruvate:carbohydrate phosphotransferase systems (PTSs). Deficiency of crr, encoding enzyme IIA of PTS, in K. pneumoniae enhanced the transcriptional activities of galF, wzi and gnd, which are in the cps gene cluster, leading to high CPS production. A crr mutant exhibited a higher survival rate in 1% hydrogen peroxide than the wild-type. The crr mutant showed less sensitivity to engulfment by macrophage (RAW 264.7) than the wild-type by observing the intracellular bacteria using confocal laser scanning microscopy (CLSM) and by calculating the colony-forming units (CFU) of intracellular bacteria. After long-term incubation, the survival rate of the intracellular crr mutant was higher than that of the wild-type. Deficiency of crr enhanced the transcriptional activities of etcABC which encodes another putative enzyme II complex of a PTS. Deletion of etcABC in the crr mutant reduced CPS production and the transcriptional activities of galF compared to those of the crr mutant. These results indicated that one PTS component, Crr, represses CPS production by repressing another PTS component, EtcABC, in K. pneumoniae. In addition, PTS plays a role in bacterial resistance to macrophage phagocytosis.


2013 ◽  
Vol 94 ◽  
pp. 451-459 ◽  
Author(s):  
Rachel Duchesne ◽  
Emeline Bouffartigues ◽  
Virginie Oxaran ◽  
Olivier Maillot ◽  
Magalie Bénard ◽  
...  

2017 ◽  
Vol 30 (6) ◽  
pp. 496 ◽  
Author(s):  
Aida Pereira ◽  
Tiago Petrucci ◽  
Maria João Simões

The hypervirulent K1 serotype Klebsiella pneumoniae is responsible for a new invasive syndrome, typically associated to hepatic abscesses with extra-hepatic complications. Initially described in Taiwan, it has significantly spread to several Asian countries and more recently to Europe and North America, thus constituting an emerging and global problem. The authors describe a case report of a 64-years-old portuguese caucasian woman without any previous diseases or epidemiological risk factors such as trips or contact with Asian products or population, diagnosed with a pyogenic liver abscess with pleural effusion caused by this hyper-virulent strain. A successful clinical cure was achieved after the etiological identification and treatment with antimicrobial therapy combined with catheter drainage. This is the first identification of hypervirulent Klebsiella pneumonia ST 23 clone in Portugal in the context of an invasive syndrome.


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