Improved 2,3-butanediol yield and productivity from lignocellulose biomass hydrolysate in metabolically engineered Enterobacter aerogenes

Enterobacter aerogenes AY-2 mutant is known for hydrogen gas producer which ws obtained from the sludge of methane fermentation and the yield is 1.5 fold higher than wildtype. Hydrogen gas production can be gain via NADH oxidation in anaerobic metabolic pathway by blocking organic acid production. Metabolic pathway can be changed by mutagenesis. Enterobacter aerogenes AY-2 mutated with ethyl methane sulfonate in logarithmic phase with consentration 10, 11, 12, 13, 14 and 15 μl/ml cell suspention during 120 minute. Mutation that result lowest survival ratio (0,01%) was 14 μl EMS/ml cell suspention is repeated with variation incubation time, 30, 60, 90 and 120 minute. 166 double mutant colony has been collected and choosen randomly. The choosen 43 colony was fermented in glycerol complex medium for determining ten double mutant with the highest H2 production. Double mutant AD-H43 is a highest H2 producer that increase 20% H2 production from AY-2 and has a decrease lactid acid production, 31% less from AY-2. Increasing H2 production in double mutant AD-H43 is caused by lactate dehydrogenase deffi cient.Keywords: Enterobacter aerogenes AY-2, ethyl methane sulfonate (EMS), H2 and methane sludge

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Антимікробна резистентність провідних збудників інфекцій сечових шляхів у Києві (Україна)

International Journal of Antibiotics and Probiotics ◽

10.31405/ijap.1-2.17.03 ◽

2017 ◽

Vol 1 (2) ◽

pp. 48-60

Author(s):

A.G. Salmanov ◽

A.V. Rudenko

Keyword(s):

Escherichia Coli ◽

Pseudomonas Aeruginosa ◽

Klebsiella Pneumoniae ◽

Staphylococcus Epidermidis ◽

Klebsiella Oxytoca ◽

Enterobacter Aerogenes ◽

Enterobacter Cloacae ◽

Proteus Vulgaris ◽

Providencia Rettgeri ◽

E Coli

Мета роботи — вивчити резистентність до антибіотиків бактеріальних збудників інфекцій сечових шляхів (ІСШ), виділених у пацієнтів урологічного стаціонару в м. Києві. Матеріали і методи. Досліджено 1612 штамів бактерій, виділених із сечі хворих з ІСШ (цистит, уретрит, пієлонефрит), госпіталізованих в урологічне відділення ДУ «Інститут урології НАМН України» у м. Києві протягом 2016 р. Серед пацієнтів переважали жінки — 1201 (74,5 %). Вік хворих становив від 17 до 74 років. Для збору даних використано медичну документацію лікарні. Мікробіологічні дослідження виконано у лабораторії мікробіології ДУ «Інститут урології НАМН України». Аналізували результати культурального дослідження зразків сечі, зібраних за наявності клінічних ознак ІСШ. Дослідження клінічного матеріалу та інтерпретацію отриманих результатів проводили загальноприйнятими методами. Вивчено чутливість уропатогенів до 31 антибіотика дискодифузійним методом відповідно до рекомендацій Інституту клінічних та лабораторних стандартів США (Clinical and Laboratory Standards Institute (CLSI)). Результати та обговорення. Аналіз мікробного спектра сечі виявив домінування серед уропатогенів штамів Escherichia coli (32,0 %), Enterococcus faecalis (19,5 %), Klebsiella pneumoniae (10,9 %), Staphylococcus epidermidis (8,9 %), S. haemolyticus (6,5 %) та Pseudomonas aeruginosa (6,4 %). Частка Enterococcus faecium, Enterobacter aerogenes і Streptococcus viridans становила відповідно 2,5, 2,2 і 1,6 %, Enterobacter cloacae, Klebsiella oxytoca, Acinetobacter baumannii, Proteus vulgaris та Providencia rettgeri — менше 1,0 %. У більшості випадків (69,7 %) мікроорганізми виділено у монокультурі, у решті випадків — у мікробних асоціа- ціях. Високу резистентність до тестованих антибіотиків виявили штами E. aerogenes (45,1 %), E. cloacae (45,7 %), E. faecium (40,9 %), E. faecalis (40,7 %), E. coli (39,9 %), P. aeruginosa (34,0 %), K. pneumoniae (28,6 %). Найбільш активними до уропатогенів були іміпенем (E. coli — 87,6 %, P. aeruginosa — 75,7 %, E. cloacae — 67,3 %, E. aerogenes — 72,6 %, K. pneumoniae — 93,2 %), меропенем (E. coli — 89,1 %, P. aeruginosa — 76,7 %, K. pneumoniae — 82,6 %), лефлоцин (E. coli — 74,5 %, ентерококи — 78,7 %, P. aeruginosa — 76,7 %, E. cloacae — 73,9 %, E. aerogenes — 80,4 %, K. pneumoniae — 83,5 %), амоксицилін/клавуланат (ентерококи — 84,6 %), фурагін (ентерококи — 82,6 %), цефоперазон (K. pneumoniae — 89,2 %, P. aeruginosa — 73,8 %), цефтріаксон (K. pneumoniae — 80,1 %). Висновки. Антибіотикорезистентність збудників ІСШ — важлива терапевтична проблема. Найбільшою активністю до уропатогенів характеризуються іміпенем, меропенем, лефлоцин, амоксицилін/ клавуланат, фурагін, цефоперазон, цефтріаксон, які можна розглядати як препарат вибору для призначення стартової терапії ІСШ. Необхідно здійснювати постійний моніторинг за резистентністю до дії антибіотиків. Політику використання антибіотиків у кожному стаціонарі слід визначати залежно від локальних даних щодо резистентності до протимікробних препаратів.

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Isolation of Stenotrophomonas maltophilia from Clinical Samples in Some Hospitals in Shiraz, Iran

Clinical and Experimental Investigations ◽

10.31487/j.cei.2020.03.01 ◽

2020 ◽

pp. 1-3

Author(s):

Majid Baserisalehi ◽

Samira Zarezadeh ◽

Majid Baserisalehi ◽

Saeed Shoa

Keyword(s):

Stenotrophomonas Maltophilia ◽

Enterobacter Aerogenes ◽

Late Summer ◽

Early Spring ◽

Clinical Samples ◽

Bacillus Species ◽

Microbiological Analysis ◽

Blood Samples ◽

Healthcare Facilities ◽

Phenotypic Methods

Stenotrophomonas maltophilia is an emerging pathogenic non-fermentative Gram-negative Bacillus species. It has caused many nosocomial infections and can be isolated from various hospital wards and healthcare facilities. Research has shown that most of its strains are inherently resistant to many antibiotics and have multidrug resistance. This research intended to determine its occurrence frequency at some Hospitals in shiraz, Iran. The present study was conducted in six months (from early spring to late summer 2019). Clinical samples (Blood, Urine and cerebrospinal fluid (CSF)) collected from 120 patients afflicted with various infections. The samples were transferred to the Laboratory and subjected to microbiological analysis. Identification of the isolates was carried out by phenotypic methods and Stenotrophomonas maltophilia isolates verified using molecular methods. In total, various bacteria were isolated from 84 clinical samples. The isolates were Escherichia coli, Enterobacter aerogenes, Klebsiella pneumoniae, Stenotrophomonas maltophilia, Staphylococcus aureus and Pseudomonas aeruginosa. Stenotrophomonas maltophilia was isolated from 17 (20.2%) positive samples and most of them were isolated from blood samples. Our finding indicated that Stenotrophomonas maltophilia isolated more from blood samples follow by CSF sample. In addition, our finding illustrated that Stenotrophomonas maltophilia can be considered as the common nosocomial agent at hospitals in Shiraz, Iran.

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Antibiotic Molecules Involved in Increasing Microbial Resistance

Revista de Chimie ◽

10.37358/rc.19.7.7392 ◽

2019 ◽

Vol 70 (7) ◽

pp. 2622-2626 ◽

Cited By ~ 5

Author(s):

Letitia Doina Duceac ◽

Constantin Marcu ◽

Daniela Luminita Ichim ◽

Irina Mihaela Ciomaga ◽

Elena Tarca ◽

...

Keyword(s):

Intensive Care ◽

Intensive Care Units ◽

Enterobacter Aerogenes ◽

Healthcare Associated Infections ◽

Medical Department ◽

Microbial Resistance ◽

Antimicrobial Sensitivity ◽

Interpretation Criteria ◽

Tract Infections ◽

Healthcare Associated

Over the past two decades, the resistance to antibiotics, especially for Gram-negative bacteria, has increased at an alarming rate, requiring constant concern for resolving and controlling this extremely important therapeutic aspect in any medical department but in particular, in Anaesthesia and Intensive Care Units, in units of neonatology, paediatrics, neurosurgery, burned patients and immunosuppressed. Specialists note a particular concern for the resistance of Enterobacteriaceae to third-generation cephalosporins and aztreonam, with a resistance profile frequently associated with the expression of extended-spectrum �-lactamases (ESBL). The Enterobacter genus comprises 14 species, but two are of medical interest, Enterobacter aerogenes and E. cloacae, which are involved in inducing healthcare-associated infections such as urinary tract infections, pneumonia associated with mechanical ventilation, bacteremia, septicemia, etc. The purpose of the study was to highlight the antibiotic molecules in which microbial resistance of some circulating strains of enterobacteria was detected. A descriptive and retrospective study was conducted between 2012-2017, on a batch of 35 patients, admitted to the Sf. Maria Emergency Clinical Hospital for Children of Iasi, from whom various pathological products were collected to highlight the Enterobacter sp strains involved in the production of infections associated with the inpatient medical care. The antimicrobial sensitivity of each strain was determined by diffusimetric method, while the interpretation criteria were considered to be those of the laboratory standards. Most cases were reported in 2017 (31.42%). The majority were registered in new-borns (42.85%) and infants (25.71%). The Anaesthesia and Intensive Care Units and Neonatology Anaesthesia and Intensive Care Units departments were the most involved. Microbial antibacterial resistance of Enterobacter sp isolates showed that all manifested resistance to ampicillin, amoxicillin and clavulanic acid, 48.57% were resistant to Cefuroxime, 42.85% resistant to Ceftazidime and Ceftriaxone, 14.28% to ciprofloxacin, 11.42% to ertapenem, 5.71% to Meronem. Although it showed relatively few cases with infections associated with healthcare in which strains of Enterobacter sp. were isolated our study, which was carried out over a period of 5 years, provides useful indications regarding the prevalence of healthcare associated infections with Enterobacter sp in paediatric patients and guidelines for antibiotic therapy.

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Green Synthesis of Silver Nanoparticles Using Artocarpus hirsutus Seed Extract and its Antibacterial Activity

Current Pharmaceutical Biotechnology ◽

10.2174/1389201021666200107115849 ◽

2020 ◽

Vol 21 (10) ◽

pp. 980-989

Author(s):

Sampath Shobana ◽

Sunderam Veena ◽

S.S.M. Sameer ◽

K. Swarnalakshmi ◽

L.A. Vishal

Keyword(s):

Silver Nanoparticles ◽

Cell Wall ◽

Antibacterial Activity ◽

Listeria Monocytogenes ◽

Nanoparticle Synthesis ◽

Enterobacter Aerogenes ◽

Seed Extract ◽

Diffusion Method ◽

Multi Drug Resistance ◽

Gastrointestinal Bacteria

Aims: To evaluate the antibacterial activity of Artocarpus hirsutus mediated seed extract for nanoparticle synthesis. Background: Gastrointestinal bacteria are known for causing deadly infections in humans. They also possess multi-drug resistance and interfere with clinical treatments. Applied nanotechnology has been known to combat such infectious agents with little interference from their special attributes. Here we synthesize silver nanoparticles from Artocarpus hirsutus seed extract against two gastro-intestinal bacterial species: Enterobacter aerogenes and Listeria monocytogenes. Objective: To collect, dry, and process seeds of Artocarpus hirsutus for nanoparticle synthesis. To evaluate the morphological interaction of silver nanoparticles with bacteria. Methods: Artocarpus hirsutus seeds were collected and processed and further silver nanoparticles were synthesized by the co-precipitation method. The synthesized nanoparticles were characterized using XRD, UV, FTIR, and SEM. These nanoparticles were employed to study the antibacterial activity of nanoparticles against Enterobacter aerogenes and Listeria monocytogenes using well diffusion method. Further, morphological interaction of silver nanoparticles on bacteria was studied using SEM. Result: Silver nanoparticles were synthesized using Artocarpus hirsutus seed extract and characterization studies confirmed that silver nanoparticles were spherical in shape with 25-40 nm size. Antibacterial study exhibited better activity against Enterobacter aerogenes with a maximum zone of inhibition than on Listeria monocytogenes. SEM micrographs indicated that Enterobacter aerogenes bacteria were more susceptible to silver nanoparticles due to the absence of cell wall. Also, the size and charge of silver nanoparticles enable easy penetration of the bacterial cell wall. Conclusion: In this study, silver nanoparticles were synthesized using the seed extract of Artocarpus hirsutus for the first time exploiting the fact that Moraceae species have high phytonutrient content which aided in nanoparticle synthesis. This nanoparticle can be employed for large scale synthesis which when coupled with the pharmaceutical industry can be used to overcome the problems associated with conventional antibiotics to treat gastrointestinal bacteria.

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Aristolochia triangularis Cham. stems and leaves essential oils and their antimicrobial and antimycobacterial effects

The Natural Products Journal ◽

10.2174/2210315510666200103123933 ◽

2020 ◽

Vol 10 ◽

Author(s):

Ionara I. Dalcol ◽

Alessandra O. Pereira ◽

Luisa H. Paz ◽

Gabriela Benetti ◽

Fallon S. Siqueira ◽

...

Keyword(s):

Chemical Composition ◽

Essential Oils ◽

Candida Glabrata ◽

Skin Diseases ◽

Enterobacter Aerogenes ◽

Gas Chromatography Mass Spectrometry ◽

Moderate Activity ◽

Circulatory System Diseases ◽

Germacrene D ◽

Stems And Leaves

Background: Aristolochia triangularis Cham., popularly known as the "cipó-mil-homens", "angelicó" and "ypê-mi", is applied for the treatment of wounds, skin diseases (6,7), digestive and circulatory system diseases as an antipyretic and for malaria fever. Objective: In this work we investigated the chemical composition, the antimicrobial and antimycobacterial activities of the essential oils (EOs) extracted from A. triangularis fresh stems and leaves collected in Southern Brazil. Methods: Fresh stems and fresh leaves of Aristolochia triangularis Cham. were separately subjected to hydrodistillation using a Clevenger-type apparatus. The chemical composition of the essential oils (EOs) were analyzed by gas chromatography/mass spectrometry (GC/MS). The oil samples were evaluated for their antimycobacterial, antibacterial and antifungal activities against twenty-four microorganisms. Results: Hydrodistillation of fresh stems and leaves of A. triangularis resulted in 0.16% (w/w) and 0.37% (w/w) respectively of light-yellow oils. Germacrene D is found in 13.2 - 13.5% in both EOs. The constituent most abundant in the stems EO (19.18%) was the oxygenated diterpene ent-Kaur-16-en-19-al (10), along with E-nerolidol (17.89%). The main constituents of the leaves EO were bicyclogermacrene (24.79%), β-elemene (11.30%), E-caryophyllene (10.40%) and germacrene A (9.42%), in addition to the previously mentioned germacrene D. The stems and leaves EOs showed capacity to inhibit the Gram-negative Enterobacter aerogenes and the stems EO capacity to inhibit Staphylococcus aureus, with MIC values of 31.2 µg/mL. S. aureus was moderately sensitive to leaves EO, while stems EO displayed moderate activity against Enterococcus faecalis and Salmonella typhimurium (MIC values of 62.5 µg/mL). Candida glabrata was highly susceptible to both EOs (MIC values < 3.9 µg/mL). The EOs showed moderate potential to inhibit the growth of Cryptococcus gatti and Cryptococcus neoformans (MICs of 62.5 μg/mL). Conclusion: The A. triangularis essential oils from stems and leaves displayed capacity to inhibit Enterobacter aerogenes (MIC values of 31.2 µg/mL) and high antifungal effect against Candida glabrata (MIC values of <3.9 µg/mL). Mycobacterium massiliense and M. abscessus were susceptible to the leaves EO, with MICs of 39.06 μg/mL. These results showed the A. triangularis essential oils potential as antifungal and antimycobacterial to be used in the development of new antibiotic.

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Omp35, a New Enterobacter aerogenes Porin Involved in Selective Susceptibility to Cephalosporins

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.48.6.2153-2158.2004 ◽

2004 ◽

Vol 48 (6) ◽

pp. 2153-2158 ◽

Cited By ~ 25

Author(s):

Charléric Bornet ◽

Nathalie Saint ◽

Lilia Fetnaci ◽

Myrielle Dupont ◽

Anne Davin-Régli ◽

...

Keyword(s):

Membrane Permeability ◽

Outer Membrane ◽

Antibiotic Susceptibility ◽

Enterobacter Aerogenes ◽

Artificial Membranes ◽

Specific Location ◽

Outer Membrane Permeability ◽

Constriction Region ◽

High Conductance

ABSTRACT In Enterobacter aerogenes, β-lactam resistance often involves a decrease in outer membrane permeability induced by modifications of porin synthesis. In ATCC 15038 strain, we observed a different pattern of porin production associated with a variable antibiotic susceptibility. We purified Omp35, which is expressed under conditions of low osmolality and analyzed its pore-forming properties in artificial membranes. This porin was found to be an OmpF-like protein with high conductance values. It showed a noticeably higher conductance compared to Omp36 and a specific location of WNYT residues in the L3 loop. The importance of the constriction region in the porin function suggests that this organization is involved in the level of susceptibility to negative large cephalosporins such as ceftriaxone by bacteria producing the Omp35 porin subfamily.

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