Exploration of Antimicrobial Potency of Mangrove Symbiont Against Multi-Drug Resistant Bacteria

Highlight ResearchAntimicrobial potential against the test microbesRhizhopora mucronata isolate showed 95% homology with Bacillus subtilis, and 97% homology with Bacillus oceanisediminis,Acanthus ilicifolius isolate showed 96% homology with Paracoccus caeni, and 89% homology with Bacillus circulans. The study found 4 isolates with antimicrobial potency against MDR pathogenic microbes.The symbiont microbes taken from Rhizophora mucronata and Acanthus ilicifolius were determined to be of the genus Bacillus and Paracoccus AbstractAntimicrobial property of mangrove symbiont have the ability to fight Multi Drug Resistant bacteria which were Staphylococcus aureus, Escherichia coli, and Vibrio haryeyi. This study aimed to determine the potential of symbiont microbes from the root of Rhizopora mucronata and Acanthus iilicifolius as antimicrobial agents against multi-drug resistant (MDR) pathogenic microbes. This research was conducted during July to November 2020. The MDR bacteria were S. aureus, E. coli, and V. harveyi MDR test microbes. The symbiont microbes were identified through molecular analyses (PCR 16S rDNA). Isolation of symbiont microbes from R. mucronata resulted in 16 isolates, while isolation from A. iilicifolius resulted in 14 isolates. Based on the antimicrobial qualitative test against S. aureus, 8 out of 16 microbial isolates from R. mucronata were found to show antimicrobial properties. The testing of A. ilicifolius symbiont microbes against S. aureus showed 8 out of 14 isolates with antimicrobial properties. The test against E. coli resulted in 2 out of 16 microbial isolates from R. mucronata and 5 out of 14 isolates from A. ilicifolius with antimicrobial properties. The test against V. harveyi resulted in two out of 16 microbial isolates from R.mucronata and 4 out of 14 isolates from A. ilicifolius with antimicrobial properties. The quantitative test found 2 isolates from R. mucronta, namely isolates RM10 and RM12, with antimicrobial properties against MDR strain E. coli, with the best isolate being RM10, which produced 11.22 mm of inhibition zone diameter. Furthermore, the selection of isolates was based on the size of the inhibition zone, the clearness of the inhibition zone and the potential for antibacterial activity. Based on their overall antimicrobial potential against the test microbes, four isolates were selected. Molecular analyses of RM12 isolate showed 95% homology with Bacillus subtilis, of RM 10 isolate showed 97% homology with Bacillus oceanisediminis, of AC isolate showed 96% homology with Paracoccus caeni, and of AC 5 isolate showed 89% homology with Bacillus circulans. The study found four isolates with antimicrobial potency against MDR pathogenic microbes. The symbiont microbes taken from R. mucronata and A. ilicifolius were determined to be of the genus Bacillus and Paracoccus.

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Agreement Assessment of Tigecycline Susceptibilities Determined by the Disk Diffusion and Broth Microdilution Methods among Commonly Encountered Resistant Bacterial Isolates: Results from the TigecyclineIn VitroSurveillance in Taiwan (TIST) Study, 2008 to 2010

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.05879-11 ◽

2011 ◽

Vol 56 (3) ◽

pp. 1414-1417 ◽

Cited By ~ 21

Author(s):

Jien-Wei Liu ◽

Wen-Chien Ko ◽

Cheng-Hua Huang ◽

Chun-Hsing Liao ◽

Chin-Te Lu ◽

...

Keyword(s):

Susceptibility Testing ◽

Total Error ◽

Error Rates ◽

Resistant Bacteria ◽

Drug Resistant ◽

Broth Microdilution ◽

Content Type ◽

E Coli ◽

Drug Resistant Bacteria

ABSTRACTThe TigecyclineIn VitroSurveillance in Taiwan (TIST) study, initiated in 2006, is a nationwide surveillance program designed to longitudinally monitor thein vitroactivity of tigecycline against commonly encountered drug-resistant bacteria. This study compared thein vitroactivity of tigecycline against 3,014 isolates of clinically important drug-resistant bacteria using the standard broth microdilution and disk diffusion methods. Species studied included methicillin-resistantStaphylococcus aureus(MRSA;n= 759), vancomycin-resistantEnterococcus faecium(VRE;n= 191), extended-spectrum β-lactamase (ESBL)-producingEscherichia coli(n= 602), ESBL-producingKlebsiella pneumoniae(n= 736), andAcinetobacter baumannii(n= 726) that had been collected from patients treated between 2008 and 2010 at 20 hospitals in Taiwan. MICs and inhibition zone diameters were interpreted according to the currently recommended U.S. Food and Drug Administration (FDA) criteria and the European Committee on Antimicrobial Susceptibility Testing (EUCAST) criteria. The MIC90values of tigecycline against MRSA, VRE, ESBL-producingE. coli, ESBL-producingK. pneumoniae, andA. baumanniiwere 0.5, 0.125, 0.5, 2, and 8 μg/ml, respectively. The total error rates between the two methods using the FDA criteria were high: 38.4% for ESBL-producingK. pneumoniaeand 33.8% forA. baumannii. Using the EUCAST criteria, the total error rate was also high (54.6%) forA. baumanniiisolates. The total error rates between these two methods were <5% for MRSA, VRE, and ESBL-producingE. coli. For routine susceptibility testing of ESBL-producingK. pneumoniaeandA. baumanniiagainst tigecycline, the broth microdilution method should be used because of the poor correlation of results between these two methods.

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Nanoparticles Enable Efficient Delivery of Antimicrobial Peptides for the Treatment of Deep Infections

BIO Integration ◽

10.15212/bioi-2021-0003 ◽

2021 ◽

Author(s):

Yingxue Deng ◽

Rui Huang ◽

Songyin Huang ◽

Menghua Xiong

Keyword(s):

Antimicrobial Peptides ◽

Broad Spectrum ◽

Antimicrobial Properties ◽

Therapeutic Index ◽

Resistant Bacteria ◽

Drug Resistant ◽

Drug Resistant Bacteria ◽

Efficient Delivery ◽

Delivery Vehicles

Antimicrobial peptides (AMPs) have emerged as promising alternatives of traditional antibiotics against drug-resistant bacteria owing to their broad-spectrum antimicrobial properties and low tendency to drugresistance. However, their therapeutic efficacy in vivo, especially for infections in deep organs, is limited owing to their systemic toxicity and low bioavailability. Nanoparticles-based delivery systems offer a strategy to increase the therapeutic index of AMPs by preventing proteolysis, increasing the accumulation at infection sites, and reducing toxicity. Herein, we will discuss the current progress of using nanoparticles as delivery vehicles for AMPs for the treatment of deep infections.

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Multifunctional divalent vancomycin: the fluorescent imaging and photodynamic antimicrobial properties for drug resistant bacteria

Chemical Communications ◽

10.1039/c0cc04434b ◽

2011 ◽

Vol 47 (5) ◽

pp. 1601-1603 ◽

Cited By ~ 58

Author(s):

Bengang Xing ◽

Tingting Jiang ◽

Wuguo Bi ◽

Yanmei Yang ◽

Lihua Li ◽

...

Keyword(s):

Antimicrobial Properties ◽

Fluorescent Imaging ◽

Resistant Bacteria ◽

Drug Resistant ◽

Drug Resistant Bacteria

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Trends in the Susceptibility of Clinically Important Resistant Bacteria to Tigecycline: Results from the TigecyclineIn VitroSurveillance in Taiwan Study, 2006 to 2010

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.06053-11 ◽

2011 ◽

Vol 56 (3) ◽

pp. 1452-1457 ◽

Cited By ~ 28

Author(s):

Yen-Hsu Chen ◽

Po-Liang Lu ◽

Cheng-Hua Huang ◽

Chun-Hsing Liao ◽

Chin-Te Lu ◽

...

Keyword(s):

Resistant Bacteria ◽

Gram Negative Bacteria ◽

Drug Resistant ◽

Content Type ◽

E Coli ◽

Drug Resistant Bacteria ◽

Vancomycin Resistant ◽

Susceptibility Rate ◽

Important Drug

ABSTRACTThe TigecyclineIn VitroSurveillance in Taiwan (TIST) study, a nationwide, prospective surveillance during 2006 to 2010, collected a total of 7,793 clinical isolates, including methicillin-resistantStaphylococcus aureus(MRSA) (n= 1,834), penicillin-resistantStreptococcus pneumoniae(PRSP) (n= 423), vancomycin-resistant enterococci (VRE) (n= 219), extended-spectrum β-lactamase (ESBL)-producingEscherichia coli(n= 1,141), ESBL-producingKlebsiella pneumoniae(n= 1,330),Acinetobacter baumannii(n= 1,645), andStenotrophomonas maltophilia(n= 903), from different specimens from 20 different hospitals in Taiwan. MICs of tigecycline were determined following the criteria of the U.S. Food and Drug Administration (FDA) and the European Committee on Antimicrobial Susceptibility Testing (EUCAST-2011). Among drug-resistant Gram-positive pathogens, all of the PRSP isolates were susceptible to tigecycline (MIC90, 0.03 μg/ml), and only one MRSA isolate (MIC90, 0.5 μg/ml) and three VRE isolates (MIC90, 0.125 μg/ml) were nonsusceptible to tigecycline. Among the Gram-negative bacteria, the tigecycline susceptibility rates were 99.65% for ESBL-producingE. coli(MIC90, 0.5 μg/ml) and 96.32% for ESBL-producingK. pneumoniae(MIC90, 2 μg/ml) when interpreted by FDA criteria but were 98.7% and 85.8%, respectively, when interpreted by EUCAST-2011 criteria. The susceptibility rate forA. baumannii(MIC90, 4 μg/ml) decreased from 80.9% in 2006 to 55.3% in 2009 but increased to 73.4% in 2010. A bimodal MIC distribution was found among carbapenem-susceptibleA. baumanniiisolates, and a unimodal MIC distribution was found among carbapenem-nonsusceptibleA. baumanniiisolates. In Taiwan, tigecycline continues to have excellentin vitroactivity against several major clinically important drug-resistant bacteria, with the exception ofA. baumannii.

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Rectal Colonization by Drug Resistant Bacteria in Nursing Home Residents in Crete, Greece

Tropical Medicine and Infectious Disease ◽

10.3390/tropicalmed6030123 ◽

2021 ◽

Vol 6 (3) ◽

pp. 123

Author(s):

Aikaterini Moschou ◽

Petros Ioannou ◽

Eleni Moraitaki ◽

Dimitra Stafylaki ◽

Sofia Maraki ◽

...

Keyword(s):

Nursing Home ◽

Nursing Home Residents ◽

Resistant Bacteria ◽

Antimicrobial Use ◽

Drug Resistant ◽

Extended Spectrum Beta Lactamase ◽

E Coli ◽

Drug Resistant Bacteria ◽

High Prevalence ◽

Rectal Colonization

(1) Background: In an area with a high prevalence of multi-drug resistant Gram-negative bacteria (MDR-GNB), we investigated the colonization of nursing home residents by such organisms. (2) Methods: A point prevalence study was performed in six nursing homes of the Heraklion area on the island of Crete. A rectal swab was taken and cultured from each participant, while additional risk factors such as recent hospitalization or antimicrobial usage were recorded and evaluated. (3) Results: A total of 137 nursing home residents were included in the study. Their mean age was 82.1 years and 19.7% were males. In total, cultures yielded 255 GNB; E. coli, K. pneumoniae and P. aeruginosa were the most common. Among the microorganisms cultured, 17.6% had the extended-spectrum beta-lactamase phenotype, while 18% were MDR. A statistically significant association was found between recent antimicrobial use and colonization by MDR-GNB; (4) Conclusions: Colonization by MDR-GNB was found to be highly prevalent in nursing home residents. Recent antimicrobial use was associated with MDR-GNB carriage.

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Identification of antibiotic-producing Bacillus sensu lato isolated from national parks of Hoang Lien and Phu Quoc in Vietnam

Journal of Vietnamese Environment ◽

10.13141/jve.vol6.no1.pp77-83 ◽

2014 ◽

Vol 6 (1) ◽

pp. 77-83

Author(s):

Thi Tuyet Van Dinh ◽

Nguyen Hai Linh Bui ◽

Van Hop Duong ◽

Mai Phuong Doan ◽

Thanh Trung Trinh

Keyword(s):

National Parks ◽

Broad Spectrum ◽

Antibiotic Production ◽

Antagonistic Activity ◽

Bacillus Species ◽

Resistant Bacteria ◽

Viet Nam ◽

Drug Resistant ◽

E Coli ◽

Drug Resistant Bacteria

Many lipopeptide antibiotics produced from Bacillus sensu lato (Bacillus s. l.) against drug-resistant bacteria have been recently reported. To explore the potential production of the antibiotics from this group of bacteria in Vietnam, we collected 38 soil samples from two national parks of Hoang Lien and Phu Quoc and isolated 411Bacillus s. l. strains. Of those, 22 strains had antagonistic activity against both susceptible S. aureus and E. coli. The strains were further tested on drug-resistant bacteria collected at Bach Mai hospital and 20 strains demonstrated antagonistic activity against at least 2 of 18 drug-resistant bacteria K. pneumoniae, E. coli, A. baumannii and S. aureus. Analysis of 16S rDNA sequence showed that most of the broad spectrum antibiotic producers were Paenibacillus species whereas narrow spectrum antibiotic producers were Bacillus species. Strains PQH 0103 and PQH 0410 were probably produced novel antibiotic agents as they suspected to be novel taxa in Paenibacillus genus. Moreover, strains PQH 1509 and PQH 1702 produced broad spectrum antibiotics were identified as P. chitinolyticus. To our best knowledge, there is no report on antibiotic production from this species. Further elucidation of chemical structure of antibiotics produced from Bacillus s. l. isolated in soils of Vietnam is needed. Gần đây, nhiều kháng sinh lipopeptide từ vi khuẩn Bacillus sensu lato (Bacillus s. l.) có khả năng sinh kháng sinh kháng vi khuẩn kháng thuốc đã được phát hiện và công bố. Để tìm hiểu khả năng sinh kháng sinh của nhóm vi khuẩn này ở Việt Nam, chúng tôi tiến hành thu thập 38 mẫu đất tại vườn Quốc gia Hoàng Liên và vườn Quốc gia Phú Quốc và phân lập được 411 chủng vi khuẩn Bacillus s. l.. Trong số đó, 22 chủng có khả năng sinh kháng sinh kháng 2 chủng vi khuẩn S. aureus và E. coli nhậy cảm thuốc. 20 trong số 22 chủng này có hoạt tính kháng ít nhất từ 2 đến 18 chủng kiểm định kháng thuốc thuộc các loài K. pneumoniae, E. coli, A. baumannii và S. aureus. Dựa trên kết quả phân loại bằng trình tự gene 16S rRNA, các chủng Bacillus s. l. sinh kháng sinh phổ rộng là các loài Paenibacillus trong khi đó các loài sinh kháng sinh phổ hẹp là Bacillus. Trên cây phát sinh chủng loại, chủng PQH 0103 và PQH 0410 có thể là những loài mới và có tiềm năng sinh các chất kháng sinh mới. Hơn nữa, chủng PQH 1509 và PQH 1702 sinh kháng sinh phổ rộng được phân loại vào loài P. chitinolyticus. Đây là loài chưa có công bố nào về khả năng sinh chất kháng sinh và có thể là loài sinh chất kháng sinh mới. Nghiên cứu giải mã cấu trúc chất kháng sinh từ các loài Bacillus s. l. phân lập tại Việt Nam cần được làm rõ trong tương lai.

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Efficacy of OH-CATH30 and Its Analogs against Drug-Resistant BacteriaIn Vitroand in Mouse Models

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.06304-11 ◽

2012 ◽

Vol 56 (6) ◽

pp. 3309-3317 ◽

Cited By ~ 38

Author(s):

Sheng-An Li ◽

Wen-Hui Lee ◽

Yun Zhang

Keyword(s):

Mouse Models ◽

Bacterial Infections ◽

Resistant Bacteria ◽

Infection Model ◽

Drug Resistant ◽

Content Type ◽

E Coli ◽

Drug Resistant Bacteria

ABSTRACTAntimicrobial peptides (AMPs) have been considered alternatives to conventional antibiotics for drug-resistant bacterial infections. However, their comparatively high toxicity toward eukaryotic cells and poor efficacyin vivohamper their clinical application. OH-CATH30, a novel cathelicidin peptide deduced from the king cobra, possesses potent antibacterial activityin vitro. The objective of this study is to evaluate the efficacy of OH-CATH30 and its analog OH-CM6 against drug-resistant bacteriain vitroandin vivo. The MICs of OH-CATH30 and OH-CM6 ranged from 1.56 to 12.5 μg/ml against drug-resistant clinical isolates of several pathogenic species, includingEscherichia coli,Pseudomonas aeruginosa, and methicillin-resistantStaphylococcus aureus. The MICs of OH-CATH30 and OH-CM6 were slightly altered in the presence of 25% human serum. OH-CATH30 and OH-CM6 killedE. coliquickly (within 60 min) by disrupting the bacterial cytoplasmic membrane. Importantly, the 50% lethal doses (LD50) of OH-CATH30 and OH-CM6 in mice following intraperitoneal (i.p.) injection were 120 mg/kg of body weight and 100 mg/kg, respectively, and no death was observed at any dose up to 160 mg/kg following subcutaneous (s.c.) injection. Moreover, 10 mg/kg OH-CATH30 or OH-CM6 significantly decreased the bacterial counts as well as the inflammatory response in a mouse thigh infection model and rescued infected mice in a bacteremia model induced by drug-resistantE. coli. Taken together, our findings demonstrate that the natural cathelicidin peptide OH-CATH30 and its analogs exhibit relatively low toxicity and potent efficacy in mouse models, indicating that they may have therapeutic potential against the systemic infections caused by drug-resistant bacteria.

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Synthesis and Study of New Quinolineaminoethanols as Anti-Bacterial Drugs

Pharmaceuticals ◽

10.3390/ph12020091 ◽

2019 ◽

Vol 12 (2) ◽

pp. 91

Author(s):

Laumaillé ◽

Dassonville-Klimpt ◽

Peltier ◽

Mullié ◽

Andréjak ◽

...

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Pseudomonas Aeruginosa ◽

Klebsiella Pneumoniae ◽

Resistant Bacteria ◽

Drug Resistant ◽

E Coli ◽

Gram Positive Bacteria ◽

Drug Resistant Bacteria ◽

Escherichia Coli Bacteria

The lack of antibiotics with a novel mode of action associated with the spread of drug resistant bacteria make the fight against infectious diseases particularly challenging. A quinoline core is found in several anti-infectious drugs, such as mefloquine and bedaquiline. Two main objectives were set in this work. Firstly, we evaluated the anti-mycobacterial properties of the previous quinolines 3, which have been identified as good candidates against ESKAPEE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, Enterobacter spp. and Escherichia coli) bacteria. Secondly, a new series 4 was designed and assessed against the same bacteria strains, taking the pair of enantiomers 3m/3n as the lead. More than twenty compounds 4 were prepared through a five-step asymmetric synthesis with good enantiomeric excesses (>90%). Interestingly, all compounds of series 3 were efficient on M. avium with MIC = 2–16 µg/mL, while series 4 was less active. Both series 3 and 4 were generally more active than mefloquine against the ESKAPEE bacteria. The quinolines 4 were either active against Gram-positive bacteria (MIC ≤ 4 µg/mL for 4c–4h and 4k/4l) or E. coli (MIC = 32–64 µg/mL for 4q–4v) according to the global lipophilicity of these compounds.

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Patterns of Drug-Resistant Bacteria in a General Hospital, China, 2011–2016

Polish Journal of Microbiology ◽

10.33073/pjm-2019-024 ◽

2019 ◽

Vol 68 (2) ◽

pp. 225-232 ◽

Cited By ~ 1

Author(s):

TINGTING MAO ◽

HUIJUAN ZHAI ◽

GUANGCAI DUAN ◽

HAIYAN YANG

Keyword(s):

General Hospital ◽

Multiple Drug Resistance ◽

Polymyxin B ◽

Resistance Rate ◽

Resistant Bacteria ◽

Multiple Drug ◽

Drug Resistant ◽

Extended Spectrum Beta Lactamase ◽

E Coli ◽

Drug Resistant Bacteria

Drug-resistant bacteria has been a threat to public life and property. We described the trends and changes in antibiotic resistance of important pathogens in a general hospital in Zhengzhou, China from 2011 to 2016, to control antimicrobial-resistant bacteria in hospital and provide support to clinicians and decision-making departments. Five dominant bacteria were enrolled based on the data from the general hospital during 6 years. The results of antimicrobial susceptibility testing were interpreted according to Clinical and Laboratory Standards Institute (CLSI). From 2011 to 2016, a total of 19,260 strains of bacteria were isolated, of which Klebsiella pneumoniae, Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Acinetobacter baumannii accounted for 51.98%. The resistance rate of K. pneumoniae and E. coli to carbapenem was less than 15%, but resistance of K. pneumoniae to carbapenems increased with time and resistance of E. coli to meropenem increased. The rate of extended-spectrum beta-lactamase (ESBL) production among K. pneumoniae and E. coli was decreasing. For most antibiotics, the resistance rate of ESBL-positive isolates was higher than that of ESBL-negative isolates, excluding carbapenems and cefoxitin. For S. aureus, the rate of methicillin-resistant S. aureus (MRSA) was stable. Resistance of S. aureus to mostly antibiotics decreased with time. Besides polymyxin B, P. aeruginosa and A. baumannii showed high resistance to other antibiotics. For A. baumannii, the resistance rate to mostly antibiotics was increasing. The bacteria showed high levels of resistance and multiple drug resistance. Continuous surveillance and optimizing the use of antibiotics are essential.

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Antibiotics can be used to contain drug-resistant bacteria by maintaining sufficiently large sensitive populations

10.1101/638924 ◽

2019 ◽

Cited By ~ 3

Author(s):

Elsa Hansen ◽

Jason Karslake ◽

Robert J. Woods ◽

Andrew F. Read ◽

Kevin B. Wood

Keyword(s):

Resistant Bacteria ◽

Escape Time ◽

Drug Resistant ◽

Threshold Density ◽

E Coli ◽

Treatment Regimens ◽

Drug Resistant Bacteria ◽

Time Required ◽

Resistant Cells

AbstractStandard infectious disease practice calls for aggressive drug treatment that rapidly eliminates the pathogen population before resistance can emerge. When resistance is absent, this elimination strategy can lead to complete cure. However, it also removes drug-sensitive cells as quickly as possible, removing competitive barriers that may slow the growth of resistant cells. In contrast to the elimination strategy, the containment strategy aims to maintain the maximum tolerable number of pathogens, exploiting competitive suppression to achieve chronic control. Here we combine in vitro experiments in computer-controlled bioreactors with mathematical modeling to investigate whether containment strategies can delay failure of antibiotic treatment regimens. To do so, we measured the “escape time” required for drug-resistant E. coli populations to eclipse a threshold density maintained by adaptive antibiotic dosing. Populations containing only resistant cells rapidly escape containment, but we found that matched populations with the maximum possible number of sensitive cells could be contained for significantly longer. The increase in escape time occurs only when the threshold density–the acceptable bacterial burden–is sufficiently high, an effect that mathematical models attribute to increased competition. The findings provide decisive experimental confirmation that maintaining the maximum number of sensitive cells can be used to contain resistance when the size of the population is sufficiently large.

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