-
Natural Products and Bioprospecting Feb 2017Among the microorganisms employed in the study, Aspergillus niger (GUFCC5443), Escherichia coli (ATCC9637), Streptomyces halstedii (CKM-2), Pseudomonas putida...
Among the microorganisms employed in the study, Aspergillus niger (GUFCC5443), Escherichia coli (ATCC9637), Streptomyces halstedii (CKM-2), Pseudomonas putida (NCIB9494), Cunninghamella elegans (NCIM689) and Sphingomonas paucimobilis (NCTC11030) were capable for the enantioselective conversion of racemic Carvedilol. Immobilization technique enhanced the enantioselectivity of microorganisms and thus increased the enantiomeric purity of the drug. Excellent enantiomeric ratios (E) were found in reactions catalyzed by immobilized A. niger and E. coli with values 174.44 and 104.26, respectively. Triacylglycerol lipase from Aspergillus niger was also employed in this study as a biocatalyst which resulted in the product with 83.35% enantiomeric excess (ee) and E of 11.34 while the enzyme on immobilization has yielded 99.08% ee and 216.39 E. The conversion yield (C%) of the drug by free-enzyme was 57.42%, which was enhanced by immobilization to 90.51%. Hence, our results suggest that immobilized triacylglycerol lipase from A. niger (Lipase AP6) could be an efficient biocatalyst for the enantioselective resolution of racemic Carvedilol to (S)-(-)-Carvedilol with high enantiomeric purity followed by immobilized cultures of A. niger and E. coli.
PubMed: 28064425
DOI: 10.1007/s13659-016-0118-2 -
Journal of Ophthalmic Inflammation and... Dec 2016Infectious endophthalmitis is a serious sight threatening intraocular inflammation that results from exogenous or endogenous spread of organisms into the eye.A...
BACKGROUND
Infectious endophthalmitis is a serious sight threatening intraocular inflammation that results from exogenous or endogenous spread of organisms into the eye.A retrospective case series to study the profile of endophthalmitis following clear corneal phacoemulsification in western India between years 2008 and 2014 was held in the National Institute of Ophthalmology, Pune, India. Cases of endophthalmitis post-clear corneal phacoemulsification were reviewed pertaining to demography, clinical history, surgeon experience, surgical complications, time of onset following surgery, duration between onset of symptoms and presentation to the center, presenting visual acuity and at follow-ups, slit-lamp examination and ultrasound findings, vitreous tap culture results, treatment, and final functional and anatomical outcomes.
RESULTS
Of 60 cases, 34 were operated in the tertiary center and 26 were referred. The incidence of endophthalmitis post clear corneal phacoemulsification performed at the tertiary center was 0.17%. Mean time delay between onset of symptoms and presentation to the tertiary care center was 2.6 days. Fifty percent cases were culture +ve, of which 80% were Gram +ve and 20% were Gram -ve, no fungal isolates. Coagulase -ve staphylococcus was the most common causative organism; rare isolates included Sphingomonas paucimobilis and Streptococcus mitis. Twenty-six eyes underwent primary vitrectomy. Mean presenting visual acuity was 2.14 ± 0.07 logMAR units which improved to logMAR 0.98 ± 0.12 at final follow-up. Presenting VA was >20/200 in 13.3% and
CONCLUSIONS
The shift of the clinico-microbiological spectrum of endophthalmitis could be due to change in surgical technique to clear corneal phacoemulsification. Predictors of good visual outcome include good presenting visual acuity, early presentation to the center, culture negativity, and coagulase negative organisms.
PubMed: 27896783
DOI: 10.1186/s12348-016-0115-y -
Plant Biotechnology Journal May 2017Lignin is a major polymer in the secondary plant cell wall and composed of hydrophobic interlinked hydroxyphenylpropanoid units. The presence of lignin hampers...
Lignin is a major polymer in the secondary plant cell wall and composed of hydrophobic interlinked hydroxyphenylpropanoid units. The presence of lignin hampers conversion of plant biomass into biofuels; plants with modified lignin are therefore being investigated for increased digestibility. The bacterium Sphingomonas paucimobilis produces lignin-degrading enzymes including LigD, LigF and LigG involved in cleaving the most abundant lignin interunit linkage, the β-aryl ether bond. In this study, we expressed the LigD, LigF and LigG (LigDFG) genes in Arabidopsis thaliana to introduce postlignification modifications into the lignin structure. The three enzymes were targeted to the secretory pathway. Phenolic metabolite profiling and 2D HSQC NMR of the transgenic lines showed an increase in oxidized guaiacyl and syringyl units without concomitant increase in oxidized β-aryl ether units, showing lignin bond cleavage. Saccharification yield increased significantly in transgenic lines expressing LigDFG, showing the applicability of our approach. Additional new information on substrate specificity of the LigDFG enzymes is also provided.
Topics: Arabidopsis; Bacterial Proteins; Gene Expression Regulation, Plant; Genetic Engineering; Glucose; Lignin; Magnetic Resonance Spectroscopy; Metabolic Networks and Pathways; Plants, Genetically Modified; Sphingomonas
PubMed: 27775869
DOI: 10.1111/pbi.12655 -
Parasitology Research Jan 2017Pathogenic free-living amoebae (FLA), such as Naegleria fowleri, Balamuthia mandrillaris and Acanthamoeba species isolated from aquatic environments have been implicated...
Pathogenic free-living amoebae (FLA), such as Naegleria fowleri, Balamuthia mandrillaris and Acanthamoeba species isolated from aquatic environments have been implicated in central nervous system, eye and skin human infections. They also allow the survival, growth and transmission of bacteria such as Legionella, Mycobacteria and Vibrio species in water systems. The purpose of this study was to investigate the co-occurrence of potentially pathogenic FLA and their associated bacteria in hospital water networks in Johannesburg, South Africa. A total of 178 water (n = 95) and swab (n = 83) samples were collected from two hospital water distribution systems. FLA were isolated using the amoebal enrichment technique and identified using PCR and 18S rDNA sequencing. Amoebae potentially containing intra-amoebal bacteria were lysed and cultured on blood agar plates. Bacterial isolates were characterized using the VITEK®2 compact System. Free-living amoebae were isolated from 77 (43.3 %) of the samples. Using microscopy, PCR and 18S rRNA sequencing, Acanthamoeba spp. (T3 and T20 genotypes), Vermamoeba vermiformis and Naegleria gruberi specie were identified. The Acanthamoeba T3 and T20 genotypes have been implicated in eye and central nervous system infections. The most commonly detected bacterial species were Serratia marcescens, Stenotrophomonas maltophilia, Delftia acidovorans, Sphingomonas paucimobilis and Comamonas testosteroni. These nosocomial pathogenic bacteria are associated with systematic blood, respiratory tract, the urinary tract, surgical wounds and soft tissues infections. The detection of FLA and their associated opportunistic bacteria in the hospital water systems point out to a potential health risk to immune-compromised individuals.
Topics: Amoeba; Bacteria; Cross Infection; Fresh Water; Hospitals; Humans; South Africa
PubMed: 27730363
DOI: 10.1007/s00436-016-5271-3 -
Le Infezioni in Medicina Sep 2016Sphingomonas paucimobilis is an aerobic, oxidase-positive, yellow-pigmented, non-fermentative, Gram-negative opportunistic pathogen that rarely causes infections in...
Sphingomonas paucimobilis is an aerobic, oxidase-positive, yellow-pigmented, non-fermentative, Gram-negative opportunistic pathogen that rarely causes infections in humans. It is commonly found in nosocomial environments and, despite its low clinical virulence, it can be responsible for several different infections especially among patients with underlying disease. Here we describe a clinical case of a 46-year-old male paraplegic patient with a history of neurogenic bladder due to insulin-dependent diabetes mellitus and renal failure who was admitted to the urology clinic of a university hospital in Kirsehir, Turkey, with the complaints of urinary tract infection (UTI) including fever, chills, dysuria, abdominal and back pain. The urine culture was positive for Sphingomonas paucimobilis identified by the Vitek-2 system and the patient was successfully treated with oral co-trimoxazole 800/160 mg twice a day for ten days associated to cefixime and fosfomycin. A literature review of UTIs associated to Sphingomonas paucimobilis is reported as well.
Topics: Anti-Bacterial Agents; Cefixime; Community-Acquired Infections; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Disease Susceptibility; Drug Therapy, Combination; Fosfomycin; Gram-Negative Bacterial Infections; Humans; Kidney Failure, Chronic; Male; Middle Aged; Opportunistic Infections; Paraplegia; Recurrence; Sphingomonas; Trimethoprim, Sulfamethoxazole Drug Combination; Turkey; Urinary Bladder, Neurogenic; Urinary Tract Infections
PubMed: 27668907
DOI: No ID Found -
Journal of Veterinary Science Dec 2016Microorganisms found in bioaerosols from animal confinement buildings not only foster the risk of spreading diseases among livestock buildings, but also pose health...
Microorganisms found in bioaerosols from animal confinement buildings not only foster the risk of spreading diseases among livestock buildings, but also pose health hazards to farm workers and nearby residents. This study identified the various microorganisms present in the air of swine, chicken, and cattle farms with different kinds of ventilation conditions in Korea. Microbial air samples were collected onto Petri dishes with bacterial or fungal growth media using a cascade impactor. Endotoxin levels in total dust were determined by the limulus amebocyte lysate kinetic QCL method. Prevalent Gram-positive bacteria were and while the dominant fungi and Gram-negative bacteria were and , respectively. Considering no significant relationship between the indoor dust endotoxin levels and the isolation of Gram-negative bacteria from the indoor air, monitoring the indoor airborne endotoxin level was found to be also critical for risk assessment on health for animals or workers. The present study confirms the importance of microbiological monitoring and control on animal husbandry indoor air to ensure animal and worker welfare.
Topics: Air Microbiology; Air Pollution, Indoor; Animal Husbandry; Animals; Bacteria; Cattle; Chickens; Dust; Endotoxins; Fungi; Housing, Animal; Humans; Occupational Exposure; Republic of Korea; Risk Assessment; Sus scrofa
PubMed: 27456779
DOI: 10.4142/jvs.2016.17.4.531 -
Scientific Reports Jul 2016Non-fermenting Gram-negative bacilli, such as Sphingomonas paucimobilis (S.paucimobilis), are among the most widespread causes of nosocomial infections. Up to now, no...
Non-fermenting Gram-negative bacilli, such as Sphingomonas paucimobilis (S.paucimobilis), are among the most widespread causes of nosocomial infections. Up to now, no definitive guidelines exist for antimicrobial therapy for S. paucimobilis infections. As we have shown that some dietary fibers exhibit pronounced immune-regulatory properties, we hypothesized that specific immune active dietary fibers might modulate the responses against S. paucimobilis. We studied the immunomodulatory effects of dietary fibers against S. paucimobilis on cytokine release and maturation of human dendritic cells (DCs) in co-cultures of DCs and intestinal epithelial cells (IECs). S. paucimobilis infection resulted in increased release of pro-inflammatory cytokines and chemokines by DCs/IECs; these effects were strongly attenuated by specific dietary fibers. Chicory inulin, sugar beet pectin, and both starches had the strongest regulatory effects. IL-12 and TNF-α were drastically diminished upon exposure to chicory inulin and sugar beet pectin, or both starches. High-maize 260, was more effective in the reduction of chemokine release than the others fibers tested. In summary, chicory inulin, sugar beet pectin, High-maize 260, and Novelose 330 attenuate S. paucimobilis-induced cytokines. These results demonstrate that dietary fibers with a specific chemical composition can be used to manage immune responses against pathogens such as S. paucimobilis.
Topics: Coculture Techniques; Cross Infection; Dendritic Cells; Dietary Fiber; Epithelial Cells; Humans; Immunomodulation; Interleukin-12; Inulin; Pectins; Sphingomonas; Starch; Tumor Necrosis Factor-alpha
PubMed: 27452116
DOI: 10.1038/srep30277 -
Applied and Environmental Microbiology Sep 2016Sphingomonas sp. strain Ndbn-20 degrades and utilizes the herbicide dicamba as its sole carbon and energy source. In the present study, a tetrahydrofolate...
UNLABELLED
Sphingomonas sp. strain Ndbn-20 degrades and utilizes the herbicide dicamba as its sole carbon and energy source. In the present study, a tetrahydrofolate (THF)-dependent dicamba methyltransferase gene, dmt, was cloned from the strain, and three other genes, metF, dhc, and purU, which are involved in THF metabolism, were found to be located downstream of dmt A transcriptional study revealed that the four genes constituted one transcriptional unit that was constitutively transcribed. Lysates of cells grown with glucose or dicamba exhibited almost the same activities, which further suggested that the dmt gene is constitutively expressed in the strain. Dmt shared 46% and 45% identities with the methyltransferases DesA and LigM from Sphingomonas paucimobilis SYK-6, respectively. The purified Dmt catalyzed the transfer of methyl from dicamba to THF to form the herbicidally inactive metabolite 3,6-dichlorosalicylic acid (DCSA) and 5-methyl-THF. The activity of Dmt was inhibited by 5-methyl-THF but not by DCSA. The introduction of a codon-optimized dmt gene into Arabidopsis thaliana enhanced resistance against dicamba. In conclusion, this study identified a THF-dependent dicamba methyltransferase, Dmt, with potential applications for the genetic engineering of dicamba-resistant crops.
IMPORTANCE
Dicamba is a very important herbicide that is widely used to control more than 200 types of broadleaf weeds and is a suitable target herbicide for the engineering of herbicide-resistant transgenic crops. A study of the mechanism of dicamba metabolism by soil microorganisms will benefit studies of its dissipation, transformation, and migration in the environment. This study identified a THF-dependent methyltransferase, Dmt, capable of catalyzing dicamba demethylation in Sphingomonas sp. Ndbn-20, and a preliminary study of its enzymatic characteristics was performed. Introduction of a codon-optimized dmt gene into Arabidopsis thaliana enhanced resistance against dicamba, suggesting that the dmt gene has potential applications for the genetic engineering of herbicide-resistant crops.
Topics: Arabidopsis; Biotransformation; Carbon; Cloning, Molecular; Dicamba; Energy Metabolism; Gene Expression Profiling; Herbicide Resistance; Methyltransferases; Multigene Family; Operon; Plants, Genetically Modified; Sphingomonas; Tetrahydrofolates; Transcription, Genetic
PubMed: 27422839
DOI: 10.1128/AEM.01201-16 -
Case Reports in Infectious Diseases 2016Sphingomonas paucimobilis is a yellow-pigmented, glucose nonfermenting, aerobic, Gram negative bacillus of low pathogenicity. This organism was found in the implantation...
Sphingomonas paucimobilis is a yellow-pigmented, glucose nonfermenting, aerobic, Gram negative bacillus of low pathogenicity. This organism was found in the implantation of indwelling catheters, sterile intravenous fluid, or contaminated hospital environment such as tap and distilled water, nebulizer, ventilator, and hemodialysis device. A 55-year-old female was hospitalized for diabetic foot ulcer in the presence of multiple comorbidities: diabetes mellitus, colonic tuberculosis, end-stage renal disease, and indwelling catheters for central venous catheter and hemodialysis. The patient passed away on the 44th day of admission due to septic shock. The organism found on blood culture on the 29th day of admission was multidrug resistant S. paucimobilis. Severe infection and septic shock due to S. paucimobilis have been reported particularly in immunocompromised patients, but there has been only one reported case of death in a premature neonate with septic shock. This is the first reported lethal case of S. paucimobilis bacteremia in an adult patient.
PubMed: 27088020
DOI: 10.1155/2016/3294639 -
Fertility and Sterility Jul 2016To study the contamination risk in open and closed vitrification devices for oocyte/embryo cryopreservation by evaluating the contaminants present (bacteria and fungi)... (Comparative Study)
Comparative Study
OBJECTIVE
To study the contamination risk in open and closed vitrification devices for oocyte/embryo cryopreservation by evaluating the contaminants present (bacteria and fungi) in the thaw medium and in liquid nitrogen (LN) storage containers.
DESIGN
Retrospective study.
SETTING
Human reproduction unit.
PATIENT(S)
None.
INTERVENTION(S)
Retrospective study of vitrification device safety and LN sterility performed from July to October 2014.
MAIN OUTCOME MEASURE(S)
From each bank container, both open and closed vitrification devices, devitrification media and LN in the containers and as supplied by the company were evaluated for contaminants. An automated system and the corresponding susceptibility to antibiotics were used for bacteria identification. Fungus detection was performed by evaluating the colony morphology and their microscopic characteristics.
RESULT(S)
No bacteria or fungi were observed in any of the devitrification media regardless of the type of device used, nor in the LN supplied by the company. No fungi were observed in any of the LN samples tested. Stenotrophomonas maltophilia and Bacillus spp. were found in all oocyte/embryo bank LN containers. There was no relationship between the number of samples or the time that each container had been used and the presence of microbiologic contaminants in the LN. At the container's bottom, Acinetobacter lwoffii, Alcaligenes faecalis ssp. faecalis, and Sphingomonas paucimobilis were found.
CONCLUSION(S)
Bacteria cross-contamination may not occur in oocyte/embryo banking in either open or closed storage devices. However, microorganisms can survive in LN. The bacteria cross-contamination risk is no greater for open than for closed containers. Storage containers should be cleaned periodically owing to the risk of lost straws or small particles of contaminated material.
Topics: Anti-Bacterial Agents; Bacteria; Cryopreservation; Embryo, Mammalian; Equipment Contamination; Equipment Design; Female; Fungi; Humans; Oocytes; Pregnancy; Retrospective Studies; Risk Assessment; Risk Factors; Vitrification
PubMed: 27025548
DOI: 10.1016/j.fertnstert.2016.03.024