The mortality rate ofAcinetobacter baumannii is as high as 47%,This is inseparable From its strong resistance to carbapenems,polymyxins,aminoglycosides,quinolone antibiotics.This article will analyze the resistance of...The mortality rate ofAcinetobacter baumannii is as high as 47%,This is inseparable From its strong resistance to carbapenems,polymyxins,aminoglycosides,quinolone antibiotics.This article will analyze the resistance of Acinetobacter baumannii to carbapenem antibiotics(meropenem and imipenem)and explore why Acinetobacter baumannii is so resistant.The data I used comes from the NCBI database,which includes six resistant groups(R)to meropenem and imipenem,and five sensitive groups(S).The level of the resistant group is complete genome,three sensitive groups are contig,and two are complete genome.Subsequently,I used Prokka in Galaxy to convert the Fasta.file into various forms such as Faa,gbk,ffn.After performing Fisher's test on all GFF files,I obtained the result chart,which includes the search for relevant domains and protein descriptions on Interpro using the chart.ProteinPlus also performed drug pocket prediction and constructed protein models using Swissmodel,as well as different multi sequence comparisons.Finally,I analyzed the functions of the proteins corresponding to the genes specific to the resistance group and the reasons for the development of drug resistance,making future research on the drug resistance of Acinetobacter baumannii easier.And further research can be conducted on the drug pocket in the protein ofAcinetobacter baumannii that has developed resistance,and drugs can be administered.展开更多
Acinetobacter(A.)baumannii is a Gram-negative,non-fermenting opportunistic pathogen increasingly implicated in nosocomial infections,particularly in intensive care units(ICUs).Its ability to acquire multidrug resistan...Acinetobacter(A.)baumannii is a Gram-negative,non-fermenting opportunistic pathogen increasingly implicated in nosocomial infections,particularly in intensive care units(ICUs).Its ability to acquire multidrug resistance(MDR),including to carbapenems,poses a major public health threat.Infections caused by A.baumannii-ranging from pneumonia to bloodstream and wound infections-are difficult to treat and associated with high mortality,especially in critically ill patients[1].展开更多
Objective:To investigate the pattern of antibiotic resistance and biofilm production capabilities of clinical Acinetobacter baumannii(A.baumannii)isolates in this study.Methods:A.baumannii isolates were collected from...Objective:To investigate the pattern of antibiotic resistance and biofilm production capabilities of clinical Acinetobacter baumannii(A.baumannii)isolates in this study.Methods:A.baumannii isolates were collected from Tehran Imam Khomeini Hospital in this cross-sectional study,and the minimum inhibitory concentrations for 16 antibiotics were determined using Vitek2®systems.All isolates were analyzed for biofilm production,then presence of biofilm-associated genes,and class Ⅰ and Ⅱ integron genes.Results:60 non-replicate A.baumannii isolates were included in this study.The resistance rates reached 100%for aztreonam,cefepime,ceftazidime,ciprofloxacin,piperacillin-tazobactam,piperacillin,ticarcillin,and trimethoprim-sulfamethoxazole.A.baumannii isolates were most sensitive to colistin and rifampicin being the most effective treatments.Multi-drug resistant and extensively drug-resistant isolates accounted for 83.3%and 16.7%,respectively.Of the isolates,91.6%formed biofilms,categorized as 10%strong,31.6%moderate,and 50%weak.No correlation was found between antibiotic resistance and biofilm formation.The genes csuE,abaI,and ompA were prevalent,but their distribution was similar across biofilm categories.A relationship between Int1 and biofilm production was noted.Conclusions:The high rates of antibiotic resistance and biofilm formation,alongside the presence of integrons including class Ⅰ and Ⅱ,underscore the necessity for ongoing monitoring of A.baumannii.Notably,classⅠintegron presence was significantly linked to biofilm formation.Further research is needed to explore the connection between antibiotic resistance and biofilm production in A.baumannii.展开更多
BACKGROUND:The Acinetobacter baumannii group,including Acinetobacter baumannii,Acinetobacter genomospecies 3 and 13 TU,is phenotypically indistinguishable and uniformly identified as Acinetobacter baumannii by laborat...BACKGROUND:The Acinetobacter baumannii group,including Acinetobacter baumannii,Acinetobacter genomospecies 3 and 13 TU,is phenotypically indistinguishable and uniformly identified as Acinetobacter baumannii by laboratories of clinical microbiology.This review aimed to demonstrate the differences among them.METHODS:Literatures associated with the Acinetobacter baumannii group were identified and selected from PubMed databases and relevant journals.RESULTS:Acinetobacter genospecies 3 and 13 TU possess a certain proportion in clinical isolates.There were considerable differences in epidemiologic features,clinical manifestations,antimicrobial resistances and therapeutic options among the Acinetobacter baumannii group.Compared with Acinetobacter genomospecies 3 and 13 TU,Acinetobacter baumannii with a higher resistance to antimicrobial agents are easier to be treated inappropriately,and present a worse outcome in patients.CONCLUSION:The Acinetobacter baumannii group comprises three distinct clinical entities,and their clinical value are not equal.展开更多
Objective Gas chromatography （GC） was used to investigate the cellular fatty acid （CFA） composition of 141 Acinetobacter boumannii and 32 A. calcoaceticus isolates from different locations in China and to find che...Objective Gas chromatography （GC） was used to investigate the cellular fatty acid （CFA） composition of 141 Acinetobacter boumannii and 32 A. calcoaceticus isolates from different locations in China and to find chemical markers to differentiate these two closely related bacteria. Methods Whole cell fatty acid methyl esters （FAMEs） were obtained by saponification, methylation, and extraction for GC analysis, followed by a standardized Microbial Identification System （MIS） analysis. Results All A. baumannii and A. calcoaceticus strains contained some major fatty acids, namely, 18：1 co9c, 16：0, Sum In Feature 3, 12：0, 17：1co8c, 3-OH-12：0, 17：0, Sum In Feature 2, 2-OH-12：0, and 18：0 compounds. Although most of the total CFAs are similar between A. baumannii and A. calcoaceticus strains, the ratios of two pairs of CFAs, i.e., Sum In Feature 3/18：1 co9c versus 16：0/18：1 co9c and Sum In Feature 3/18：1 co9c versus unknown 12.484/18：1 co9c fatty acids, could differentiate these two closely related bacteria. A. baumannii could be easily classified into two subgroups by plotting some ratios such as Sum In Feature 3/16：0 versus 17：0 and Sum In Feature 3/2-OH-12：0 versus17：0 fatty acids. Conclusion The ratios of some CFAs could be used as chemical markers to distinguish A. baumannii from A. colcoaceticus.展开更多
Objective: To determine the antibiotic resistance patterns of the Acinetobacter(A.) baumannii complex isolates that cause the confirmed infection. Methods: The present descriptive study was performed from March 2016 t...Objective: To determine the antibiotic resistance patterns of the Acinetobacter(A.) baumannii complex isolates that cause the confirmed infection. Methods: The present descriptive study was performed from March 2016 to March 2018 in three referral hospitals in Isfahan, Iran. All A. baumannii complex strains isolated from different clinical samples were identified by conventional phenotypic methods and antibiotic susceptibility pattern was detected. After the clinical investigation, contaminated samples were excluded and the source(hospital/community) and site of the infection were determined. Data on antibiotic susceptibility testing were extracted from WHONET software and analysis was done with SPSS.Results: From 254 patients who had confirmed A. baumannii complex infection, 158(62.20%) cases were male, 27(10.63%) were less than 20 years old, 172(67.72%) had healthcare-associated infections and 96(37.79%) were admitted in intensive care units. The most frequent infection was bloodstream infections(111, 43.70%). Our results showed that most of the isolates were resistant to most of the antibiotics(more than 75.00%) and a lower rate of non-susceptibility was observed against minocycline(20, 44.44%) and colistin(0%). The rate of multidrug-resistant isolates was 88.97%. There was no significant difference between resistance of A. baumannii complex isolates according to age. However, the resistance to amikacin and minocycline and the rate of multidrug resistance(MDR) were significantly different between males and females. In patients with healthcare associated infection(HAI), MDR isolates were significantly different regarding admission in ICU ward. Resistance to levofloxacin and ciprofloxacin were lower in isolates from patients with bloodstream infections in comparison to other diagnoses.Conclusions: In our study, a high level of antibiotic resistance was detected in both community-acquired and healthcare-associated A. baumannii complex infections. Appropriate antibiotic prescription in a clinical setting is an essential need for the control and prevention of A. baumannii resistant infections.展开更多
Acinetobacter baumannii(A. baumannii) is undoubtedly one of the most successful pathogens in the modern healthcare system. With invasive procedures, antibiotic use and immunocompromised hosts increasing in recent year...Acinetobacter baumannii(A. baumannii) is undoubtedly one of the most successful pathogens in the modern healthcare system. With invasive procedures, antibiotic use and immunocompromised hosts increasing in recent years, A. baumannii has become endemic in hospitals due to its versatile genetic machinery, which allows it to quickly evolve resistance factors, and to its remarkable ability to tolerate harsh environments. Infections and outbreaks caused by multidrugresistant A. baumannii(MDRAB) are prevalent and have been reported worldwide over the past twenty or more years. To address this problem effectively, knowledge of species identification, typing methods, clinical manifestations, risk factors, and virulence factors is essential. The global epidemiology of MDRAB is monitored by persistent surveillance programs. Because few effective antibiotics are available, clinicians often face serious challenges when treating patients with MDRAB. Therefore, a deep understanding of the resistance mechanisms used by MDRAB can shed light on two possible strategies to combat the dissemination of antimicrobial resistance: stringent infection control and antibiotic treatments, of which colistin-based combination therapy is the mainstream strategy. However, due to the current unsatisfying therapeutic outcomes, there is a great need to develop and evaluate the efficacy of new antibiotics and to understand the role of other potential alternatives, such as antimicrobial peptides, in the treatment of MDRAB infections.展开更多
A new phenol-degrading bacterium with high biodegradation activity and high tolerance of phenol, strain PD 12, was isolated from the activated sludge of Tianjin Jizhuangzi Wastewater Treatment Facility in China. This ...A new phenol-degrading bacterium with high biodegradation activity and high tolerance of phenol, strain PD 12, was isolated from the activated sludge of Tianjin Jizhuangzi Wastewater Treatment Facility in China. This strain was capable of removing 500 mg phenol/L in liquid minimal medium by 99.6% within 9 h and metabolizing phenol at concentrations up to 1100 mg/L. DNA sequencing and homologous analysis of 16S rRNA gene identified PD12 to be an Acinetobacter sp. Polyvinyl alcohol （PVA） was used as a gel matrix to immobilize Acinetobacter sp. strain PDI2 by repeated freezing and thawing. The factors affecting phenol degradation of immobilized cells were investigated, and the results showed that the immobilized cells could tolerate a high phenol level and protected the bacteria against changes in temperature and pH. Storage stability and reusability tests revealed that the phenol degradation functions of immobilized cells were stable after reuse for 50 times or storing at 4℃ for 50 d. These results indicate that immobilized Acinetobacter sp. strain PD 12 possesses a good application potential in the treatment of phenol-containing wastewater.展开更多
文摘The mortality rate ofAcinetobacter baumannii is as high as 47%,This is inseparable From its strong resistance to carbapenems,polymyxins,aminoglycosides,quinolone antibiotics.This article will analyze the resistance of Acinetobacter baumannii to carbapenem antibiotics(meropenem and imipenem)and explore why Acinetobacter baumannii is so resistant.The data I used comes from the NCBI database,which includes six resistant groups(R)to meropenem and imipenem,and five sensitive groups(S).The level of the resistant group is complete genome,three sensitive groups are contig,and two are complete genome.Subsequently,I used Prokka in Galaxy to convert the Fasta.file into various forms such as Faa,gbk,ffn.After performing Fisher's test on all GFF files,I obtained the result chart,which includes the search for relevant domains and protein descriptions on Interpro using the chart.ProteinPlus also performed drug pocket prediction and constructed protein models using Swissmodel,as well as different multi sequence comparisons.Finally,I analyzed the functions of the proteins corresponding to the genes specific to the resistance group and the reasons for the development of drug resistance,making future research on the drug resistance of Acinetobacter baumannii easier.And further research can be conducted on the drug pocket in the protein ofAcinetobacter baumannii that has developed resistance,and drugs can be administered.
基金supported by ICMR-RMRC intramural fund(RMRC/IM/2022/26).
文摘Acinetobacter(A.)baumannii is a Gram-negative,non-fermenting opportunistic pathogen increasingly implicated in nosocomial infections,particularly in intensive care units(ICUs).Its ability to acquire multidrug resistance(MDR),including to carbapenems,poses a major public health threat.Infections caused by A.baumannii-ranging from pneumonia to bloodstream and wound infections-are difficult to treat and associated with high mortality,especially in critically ill patients[1].
基金This study was financially supported by the Vice Chancellor for Research Affairs,Ilam University of Medical Sciences,Ilam,Iran(Project No.1326).
文摘Objective:To investigate the pattern of antibiotic resistance and biofilm production capabilities of clinical Acinetobacter baumannii(A.baumannii)isolates in this study.Methods:A.baumannii isolates were collected from Tehran Imam Khomeini Hospital in this cross-sectional study,and the minimum inhibitory concentrations for 16 antibiotics were determined using Vitek2®systems.All isolates were analyzed for biofilm production,then presence of biofilm-associated genes,and class Ⅰ and Ⅱ integron genes.Results:60 non-replicate A.baumannii isolates were included in this study.The resistance rates reached 100%for aztreonam,cefepime,ceftazidime,ciprofloxacin,piperacillin-tazobactam,piperacillin,ticarcillin,and trimethoprim-sulfamethoxazole.A.baumannii isolates were most sensitive to colistin and rifampicin being the most effective treatments.Multi-drug resistant and extensively drug-resistant isolates accounted for 83.3%and 16.7%,respectively.Of the isolates,91.6%formed biofilms,categorized as 10%strong,31.6%moderate,and 50%weak.No correlation was found between antibiotic resistance and biofilm formation.The genes csuE,abaI,and ompA were prevalent,but their distribution was similar across biofilm categories.A relationship between Int1 and biofilm production was noted.Conclusions:The high rates of antibiotic resistance and biofilm formation,alongside the presence of integrons including class Ⅰ and Ⅱ,underscore the necessity for ongoing monitoring of A.baumannii.Notably,classⅠintegron presence was significantly linked to biofilm formation.Further research is needed to explore the connection between antibiotic resistance and biofilm production in A.baumannii.
基金supported by a from grant Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)
文摘BACKGROUND:The Acinetobacter baumannii group,including Acinetobacter baumannii,Acinetobacter genomospecies 3 and 13 TU,is phenotypically indistinguishable and uniformly identified as Acinetobacter baumannii by laboratories of clinical microbiology.This review aimed to demonstrate the differences among them.METHODS:Literatures associated with the Acinetobacter baumannii group were identified and selected from PubMed databases and relevant journals.RESULTS:Acinetobacter genospecies 3 and 13 TU possess a certain proportion in clinical isolates.There were considerable differences in epidemiologic features,clinical manifestations,antimicrobial resistances and therapeutic options among the Acinetobacter baumannii group.Compared with Acinetobacter genomospecies 3 and 13 TU,Acinetobacter baumannii with a higher resistance to antimicrobial agents are easier to be treated inappropriately,and present a worse outcome in patients.CONCLUSION:The Acinetobacter baumannii group comprises three distinct clinical entities,and their clinical value are not equal.
基金supported by the Innovation Foundation of Shanxi Medical University for undergraduate students (No. 2009056)the National Key Program for Infectious Diseases of China (No. 2008ZX10004-009)
文摘Objective Gas chromatography （GC） was used to investigate the cellular fatty acid （CFA） composition of 141 Acinetobacter boumannii and 32 A. calcoaceticus isolates from different locations in China and to find chemical markers to differentiate these two closely related bacteria. Methods Whole cell fatty acid methyl esters （FAMEs） were obtained by saponification, methylation, and extraction for GC analysis, followed by a standardized Microbial Identification System （MIS） analysis. Results All A. baumannii and A. calcoaceticus strains contained some major fatty acids, namely, 18：1 co9c, 16：0, Sum In Feature 3, 12：0, 17：1co8c, 3-OH-12：0, 17：0, Sum In Feature 2, 2-OH-12：0, and 18：0 compounds. Although most of the total CFAs are similar between A. baumannii and A. calcoaceticus strains, the ratios of two pairs of CFAs, i.e., Sum In Feature 3/18：1 co9c versus 16：0/18：1 co9c and Sum In Feature 3/18：1 co9c versus unknown 12.484/18：1 co9c fatty acids, could differentiate these two closely related bacteria. A. baumannii could be easily classified into two subgroups by plotting some ratios such as Sum In Feature 3/16：0 versus 17：0 and Sum In Feature 3/2-OH-12：0 versus17：0 fatty acids. Conclusion The ratios of some CFAs could be used as chemical markers to distinguish A. baumannii from A. colcoaceticus.
文摘Objective: To determine the antibiotic resistance patterns of the Acinetobacter(A.) baumannii complex isolates that cause the confirmed infection. Methods: The present descriptive study was performed from March 2016 to March 2018 in three referral hospitals in Isfahan, Iran. All A. baumannii complex strains isolated from different clinical samples were identified by conventional phenotypic methods and antibiotic susceptibility pattern was detected. After the clinical investigation, contaminated samples were excluded and the source(hospital/community) and site of the infection were determined. Data on antibiotic susceptibility testing were extracted from WHONET software and analysis was done with SPSS.Results: From 254 patients who had confirmed A. baumannii complex infection, 158(62.20%) cases were male, 27(10.63%) were less than 20 years old, 172(67.72%) had healthcare-associated infections and 96(37.79%) were admitted in intensive care units. The most frequent infection was bloodstream infections(111, 43.70%). Our results showed that most of the isolates were resistant to most of the antibiotics(more than 75.00%) and a lower rate of non-susceptibility was observed against minocycline(20, 44.44%) and colistin(0%). The rate of multidrug-resistant isolates was 88.97%. There was no significant difference between resistance of A. baumannii complex isolates according to age. However, the resistance to amikacin and minocycline and the rate of multidrug resistance(MDR) were significantly different between males and females. In patients with healthcare associated infection(HAI), MDR isolates were significantly different regarding admission in ICU ward. Resistance to levofloxacin and ciprofloxacin were lower in isolates from patients with bloodstream infections in comparison to other diagnoses.Conclusions: In our study, a high level of antibiotic resistance was detected in both community-acquired and healthcare-associated A. baumannii complex infections. Appropriate antibiotic prescription in a clinical setting is an essential need for the control and prevention of A. baumannii resistant infections.
文摘Acinetobacter baumannii(A. baumannii) is undoubtedly one of the most successful pathogens in the modern healthcare system. With invasive procedures, antibiotic use and immunocompromised hosts increasing in recent years, A. baumannii has become endemic in hospitals due to its versatile genetic machinery, which allows it to quickly evolve resistance factors, and to its remarkable ability to tolerate harsh environments. Infections and outbreaks caused by multidrugresistant A. baumannii(MDRAB) are prevalent and have been reported worldwide over the past twenty or more years. To address this problem effectively, knowledge of species identification, typing methods, clinical manifestations, risk factors, and virulence factors is essential. The global epidemiology of MDRAB is monitored by persistent surveillance programs. Because few effective antibiotics are available, clinicians often face serious challenges when treating patients with MDRAB. Therefore, a deep understanding of the resistance mechanisms used by MDRAB can shed light on two possible strategies to combat the dissemination of antimicrobial resistance: stringent infection control and antibiotic treatments, of which colistin-based combination therapy is the mainstream strategy. However, due to the current unsatisfying therapeutic outcomes, there is a great need to develop and evaluate the efficacy of new antibiotics and to understand the role of other potential alternatives, such as antimicrobial peptides, in the treatment of MDRAB infections.
基金Project supported by the Undergraduate Research Foundation of Nankai University (2004).
文摘A new phenol-degrading bacterium with high biodegradation activity and high tolerance of phenol, strain PD 12, was isolated from the activated sludge of Tianjin Jizhuangzi Wastewater Treatment Facility in China. This strain was capable of removing 500 mg phenol/L in liquid minimal medium by 99.6% within 9 h and metabolizing phenol at concentrations up to 1100 mg/L. DNA sequencing and homologous analysis of 16S rRNA gene identified PD12 to be an Acinetobacter sp. Polyvinyl alcohol （PVA） was used as a gel matrix to immobilize Acinetobacter sp. strain PDI2 by repeated freezing and thawing. The factors affecting phenol degradation of immobilized cells were investigated, and the results showed that the immobilized cells could tolerate a high phenol level and protected the bacteria against changes in temperature and pH. Storage stability and reusability tests revealed that the phenol degradation functions of immobilized cells were stable after reuse for 50 times or storing at 4℃ for 50 d. These results indicate that immobilized Acinetobacter sp. strain PD 12 possesses a good application potential in the treatment of phenol-containing wastewater.
