31 research outputs found
Comparison of S. aureus Proteomic Profiles from Biofilm and Planktonic Growth Conditions using 2D- Gel Electrophoresis.
No full textMolecular analysis of the role of Haemophilus influenzae porin P2 in host-pathogen interactions
No full textHaemophilus influenzae type b (Hib) was a main cause of bacterial meningitis. Together with Neisseria meningitidis and Streptococcus pneumoniae, it occurred with comparable frequency prior to the introduction of conjugated polysaccharide vaccines against Hib. Despite the fact that the introduction of conjugated vaccines against Hib has virtually eradicated infection in many areas of the globe, this pathogen still causes many infections in developing countries and a number of cases of infection have been reported in fully vaccinated children in developed countries. Recent studies have focused on the mechanisms by which these pathogens invade the central nervous system through the blood brain barrier (BBB). One study revealed that the outer membrane protein OmpP2 of H. influenzae interacted with the 37/67-kDa non-integrin laminin receptor (LamR) of human brain microvascular endothelial cells (HBMECs). In this study, OmpP2 of H. influenzae was expressed and purified and its interactions with purified recombinant LamR (rLamR) were analysed. OmpP2, which is predicted to contain eight extracellular loops, was expressed in two parts: OmpP2Δ1-4, lacking loops 1-4, and OmpP2Δ5-8, lacking loops 5-8. The protein fragments were purified and their interaction with rLamR was investigated by ELISA. The LamR binding site of OmpP2 was found to be restricted to loops 1-4. Therefore, ompP2 derivatives encoding OmpP2 lacking loops 1, 2, 3 and 4 individually, were constructed. The OmpP2 derivatives were expressed and tested in rLamR-binding assays to determine which of these loops is required for LamR binding. Only OmpP2∆L2 showed dramatically decreased binding to rLamR. Accordingly, loop 2 of OmpP2 may play an important role in the interaction of H. influenzae with LamR. Therefore, ompP2 and ompP2ΔL2 null mutants were generated in H. influenzae strain Rd KW20 and utilized in subsequent characterization experiments to facilitate a study of the potential role of OmpP2 and its second loop in the pathogenesis of H. influenzae. The interaction of H. influenzae and its derivative mutants to LamR was investigated using a combination of molecular and immunological techniques, including ELISA, whole cell lysate pull-down assays, invasion and association assays and flow cytometry. H. influenzae cells either lacking OmpP2 or expressing OmpP2∆L2 showed significantly reduced rLamR-binding compared to the wild type. Furthermore, synthetic peptides based on the loop 2 sequence coupled to micro-beads mediated adherence of the beads to HBMECs. The amino acid sequence of OmpP2 loop 2 was found to be highly conserved in Hib isolates, but not in non-typeable H. influenzae, which rarely cause invasive disease. The potential roles of OmpP2 and Loop 2 in H. influenzae pathogenesis are discussed
Molecular analysis of the role of Haemophilus influenzae porin P2 in host-pathogen interactions
No full textHaemophilus influenzae type b (Hib) was a main cause of bacterial meningitis. Together with Neisseria meningitidis and Streptococcus pneumoniae, it occurred with comparable frequency prior to the introduction of conjugated polysaccharide vaccines against Hib. Despite the fact that the introduction of conjugated vaccines against Hib has virtually eradicated infection in many areas of the globe, this pathogen still causes many infections in developing countries and a number of cases of infection have been reported in fully vaccinated children in developed countries. Recent studies have focused on the mechanisms by which these pathogens invade the central nervous system through the blood brain barrier (BBB). One study revealed that the outer membrane protein OmpP2 of H. influenzae interacted with the 37/67-kDa non-integrin laminin receptor (LamR) of human brain microvascular endothelial cells (HBMECs). In this study, OmpP2 of H. influenzae was expressed and purified and its interactions with purified recombinant LamR (rLamR) were analysed. OmpP2, which is predicted to contain eight extracellular loops, was expressed in two parts: OmpP2Δ1-4, lacking loops 1-4, and OmpP2Δ5-8, lacking loops 5-8. The protein fragments were purified and their interaction with rLamR was investigated by ELISA. The LamR binding site of OmpP2 was found to be restricted to loops 1-4. Therefore, ompP2 derivatives encoding OmpP2 lacking loops 1, 2, 3 and 4 individually, were constructed. The OmpP2 derivatives were expressed and tested in rLamR-binding assays to determine which of these loops is required for LamR binding. Only OmpP2∆L2 showed dramatically decreased binding to rLamR. Accordingly, loop 2 of OmpP2 may play an important role in the interaction of H. influenzae with LamR. Therefore, ompP2 and ompP2ΔL2 null mutants were generated in H. influenzae strain Rd KW20 and utilized in subsequent characterization experiments to facilitate a study of the potential role of OmpP2 and its second loop in the pathogenesis of H. influenzae. The interaction of H. influenzae and its derivative mutants to LamR was investigated using a combination of molecular and immunological techniques, including ELISA, whole cell lysate pull-down assays, invasion and association assays and flow cytometry. H. influenzae cells either lacking OmpP2 or expressing OmpP2∆L2 showed significantly reduced rLamR-binding compared to the wild type. Furthermore, synthetic peptides based on the loop 2 sequence coupled to micro-beads mediated adherence of the beads to HBMECs. The amino acid sequence of OmpP2 loop 2 was found to be highly conserved in Hib isolates, but not in non-typeable H. influenzae, which rarely cause invasive disease. The potential roles of OmpP2 and Loop 2 in H. influenzae pathogenesis are discussed
Comparison of S. aureus Proteomic Profiles from Biofilm and Planktonic Growth Conditions using 2D- Gel Electrophoresis.
No full textBacteria growing as biofilms are distinct from the same bacteria growing as planktonic cells. Biofilms cells show increased resistance to antimicrobial, immunological, predatory, and chemical attack than planktonic cells. Most studies on bacterial diseases use planktonic bacteria. The objective of this study was to identify expressed proteins that are unique to Staphylococcus aureus biofilm mode of growth. S. aureus was grown in tryptic soy broth and Dulbecco's modified eagle medium at biofilm and planktonic growth conditions. Protein samples were cleaned up and separated according to their electrophoretic mobility using 7 cm IPG strips (pH 3–10 and pH 4–7) on 2D gel electrophoresis. Expressed proteins of both growth conditions were compared. Data analysis revealed that the expression of S. aureus proteins from planktonic and biofilm was higher in TSB media than DMEM media. Biofilm growth condition showed higher intensity of expressed proteins and new expressed proteins were observed. One protein was found to be upregulated in planktonic growth condition. Additionally, the majority of the proteins were clustered in the area of acidic region (pH 4–7). 2D-gel electrophoresis is a powerful and widely used method for the proteomic analysis. Biofilms represent a realistic representation of bacterial behavior and organisms are capable of altering their physiology in the surrounded environments. The results could help to illustrate the differences in pathogenesis between biofilm and planktonic cells in any model of disease. This will identify biological markers to improve the diagnostics, treatment, and prevention of S. aureus biofilms
Oral carriage of Staphylococcus aureus in people with different body mass index
No full textBackground: The association between obesity and the oral microbiome has received great attention. Objective: This study aimed to determine the association of oral Staphylococcus aureus with different body mass index people. Material and Methods: A total of 155 saliva samples were collected. The individuals were grouped into three categories according to their BMI, normal weight, overweight and obese individuals. A loopful of saliva sample was cultured and incubated at 37 °C for 24. Staphylococcus aureus isolates were diagnosed by colony characteristics, morphology, and biochemical tests. Results: The oral carriage rate of Staphylococcus aureus was 61.3% (65.1% females and 56.5% males). The Staphylococcus aureus rate was 68% in married and 60% in single people. The differences of oral carriage rates of Staphylococcus aureus in obese (73.6%) and overweight (85.4%) populations was statistically significant (p<0.0001) compared to the rate in normal weight group (34%). Among males, the highest oral carriage rate of Staphylococcus aureus was in overweight individuals (82.6%). Likewise, in females, the highest rate of salivary Staphylococcus aureus was among the overweight group (88.9%). Regarding marital status, in single people, the differences of Staphylococcus aureus in obese (p=0.0003) and overweight (p<0.0001) people was significantly compared to normal weight people. But, in married people, the differences in Staphylococcus aureus rates among all groups were statistically not significant (p=0.0935). Conclusion: Staphylococcus aureus was significantly related to overweight and obese individuals. The human oral Staphylococcus aureus may play a key role in the manifestation of obesity. The oral microbiota could provide a new target for improving the physical well being of humans
Prevalence and antimicrobial susceptibility patterns of uropathogenic E. coli among people in Zakho, Iraq
No full textBackground: Antimicrobial resistance in uropathogenic E. coli is of major concern worldwide due to its increasing resistance to several commonly prescribed antibiotics. The aims of this study were to determine the prevalence and to evaluate the presence and antibiogram pattern of uropathogenic E. coli among people in Zakho city, Iraq.Methods: 1120 urine samples were collected from people. Samples were screened for E. coli isolates and their susceptibility to different antibiotics was analyzed.Results: Diagnoses tests showed that only 106 (9.4%) isolates were E. coli. Females (90, 85%) were more susceptible to urinary tract infections (UTIs) than males (16, 15%) (p <0.05). The age 11-21 years old (23, 21.7%) was the most affected group (p <0.05). All isolates were resistant to penicillin, ampicillin and aztreonam. While, all these isolates were sensitive to imipenem and meropenem.Conclusions: The incidence of uropathogenic E. coli among people is comparable with reports from elsewhere. E. coli isolates are highly susceptible towards imipenem, and meropenem antibiotics, and highly resistant towards β-lactam and cephalosporins antibiotics. Education programs and improving the hygienic measures are necessary to prevent contaminations with E. coli and minimize the use of β-lactam and cephalosporin antibiotics
Oral carriage of Staphylococcus aureus in people with different body mass index
No full textBackground: The association between obesity and the oral microbiome has received great attention. Objective: This study aimed to determine the association of oral Staphylococcus aureus with different body mass index people. Material and Methods: A total of 155 saliva samples were collected. The individuals were grouped into three categories according to their BMI, normal weight, overweight and obese individuals. A loopful of saliva sample was cultured and incubated at 37°C for 24. Staphylococcus aureus isolates were diagnosed by colony characteristics, morphology, and biochemical tests. Results: The oral carriage rate of Staphylococcus aureus was 61.3% (65.1% females and 56.5% males). The Staphylococcus aureus rate was 68% in married and 60% in single people. The differences of oral carriage rates of Staphylococcus aureus in obese (73.6%) and overweight (85.4%) populations was statistically significant (p<0.0001) compared to the rate in normal weight group (34%). Among males, the highest oral carriage rate of Staphylococcus aureus was in overweight individuals (82.6%). Likewise, in females, the highest rate of salivary Staphylococcus aureus was among the overweight group (88.9%). Regarding marital status, in single people, the differences of Staphylococcus aureus in obese (p=0.0003) and overweight (p<0.0001) people was significantly compared to normal weight people. But, in married people, the differences in Staphylococcus aureus rates among all groups were statistically not significant (p=0.0935). Conclusion: Staphylococcus aureuswas significantly related to overweight and obese individuals. The human oral Staphylococcus aureus may play a key role in the manifestation of obesity. The oral microbiota could provide a new target for improving the physical well being of humans.Antecedentes: la asociación entre la obesidad y el microbioma oral ha recibido gran atención. Objetivo: Este estudio tuvo como objetivo determinar la asociación de Staphylococcus aureus oral en personas con diferentes índices de masa corporal. Material y Métodos: Se recolectaron un total de 155 muestras de saliva. Los individuos fueron agrupados en tres categorías según su indice de masa corporal: normopeso, sobrepeso y obesos. Se cultivó un asa de muestra de saliva y se incubó a 37°C durante 24 horas. Los aislamientos de Staphylococcus aureus se identificaron mediante las características de la colonia, la morfología y las pruebas bioquímicas. Resultados:La tasa de colonización oral por Staphylococcus aureus fue del 61,3% (65,1% mujeres y 56,5% hombres). La tasa de colonización por Staphylococcus aureus fue del 68% en casados y del 60% en solteros. Las diferencias de las tasas de portación oral de Staphylococcus aureus en las poblaciones obesas (73,6%) y con sobrepeso (85,4%) fueron estadísticamente significativas (p<0,0001) en comparación con la tasa en el grupo de peso normal (34.0%). Entre los hombres, la tasa más alta de portadores orales de Staphylococcus aureusfue en individuos con sobrepeso (82,6%). En las mujeres, la tasa más alta de Staphylococcus aureus salival se también se presentó en el grupo con sobrepeso (88,9 %). En cuanto al estado civil, en solteros, las diferencias de Staphylococcus aureus en obesos (p=0,0003) y con sobrepeso (p<0,0001) fueron significativas compararadas con normopeso. Pero, en personas casadas, las diferencias en las tasas de Staphylococcus aureus entre todos los grupos no fueron estadísticamente significativas (p=0,0935). Conclusion: Staphylococcus aureus salival se relacionó significativamente en individuos con sobrepeso y obesidad. El Staphylococcus aureus oral humano puede jugar un papel clave en la manifestación de la obesidad. La microbiota oral podría proporcionar una nueva diana para mejorar el estado físico de los humanos
The frequency of the pathogenic bacteria isolated from different clinical samples in Duhok, Iraq
No full textThe Prevalence, Molecular Characterization and Antimicrobial Susceptibility of S. aureus Isolated from Impetigo Cases in Duhok, Iraq
No full textBackground:Staphylococcus aureusis one of the most important opportunistic pathogens. Impetigo is the common contagious bacterial infection of the skin caused byS. aureus.Method:Samples were taken from 204 patients with impetigo disease.S. aureusisolates were tested for their antimicrobial susceptibility. Genomic DNA ofS. aureuswas used to transformE. coliHB101 strain and expression capability ofS. aureusplasmids in transformedE. coliwas investigated. 68.62% (140/204) of the specimens were nonbullous impetigo and 31.38% (64/204) were bullous impetigo.S. aureusstrains were isolated from 41.66% (85/204) of impetigo cases (82.35% from nonbullous and 17.65% from the bullous impetigo). There was an inverse relationship between the incidence ofS. aureusisolated and age.Result:Three biotypes ofS. aureuswere identified based on their fermentation of different sugars. All isolates were resistant to penicillin and most isolates were resistant to ampicillin (95.3%), amoxicillin, (94.11%) and cephalexin (90.95%). Most isolates were sensitive against vancomycin and rifampicin (98.83%). 5.88% (5/85) ofS. aureusisolates were identified as MRSA. A maximum of 5 markers fromS. aureusisolates were capable to be expressed in transformedE. coliHB101 strains. The incidence of impetigo caused byS. aureusis comparable with reports from elsewhere.S. aureusisolates showed multidrug resistance against antibiotics.Conclusion:Plasmids ofS. aureusare capable to show its expression inE. coliHB101. Molecular study is needed to investigate the role of plasmids in different patterns of multi drug resistance.</jats:sec
Prevalence and molecular characterization of extended spectrum beta-Lactamases-producing uropathogenic Escherichia coli isolated in Zakho, Iraq
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