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1.
Front Microbiol ; 15: 1331120, 2024.
Article En | MEDLINE | ID: mdl-38468850

Currently, there is a growing interest in transforming wastewater treatment plants (WWTPs) into resource recovery plants. Microorganisms in aerobic granular sludge produce extracellular polymeric substances (EPS), which are considered sustainable resources to be extracted and can be used in diverse applications. Exploring applications in other high-value materials, such as adhesives, will not only enhance the valorization potential of the EPS but also promote resource recovery. This study aimed to characterize a water-soluble fraction extracted from the EPS collected at the demonstration plant in the Netherlands based on its chemical composition (amino acids, sugar, and fatty acids) and propose a proof-of-concept for its use as an adhesive. This fraction comprises a mixture of biomolecules, such as proteins (26.6 ± 0.3%), sugars (21.8 ± 0.2%), and fatty acids (0.9%). The water-soluble fraction exhibited shear strength reaching 36-51 kPa across a pH range of 2-10 without additional chemical treatment, suggesting a potential application as an adhesive. The findings from this study provide insights into the concept of resource recovery and the valorization of excess sludge at WWTPs.

2.
J Chromatogr A ; 1710: 464425, 2023 Nov 08.
Article En | MEDLINE | ID: mdl-37844367

The technological advances of analytical instrumentation and techniques has laid the ground for the rapid expansion of metabolomics or in a wider sense, untargeted analysis applied to life sciences themes. However, the objective of identifying all existing metabolites within organisms remains a daunting challenge. All analytical techniques exhibit varying degrees of sensitivity and versatility for the detection of metabolites and none of the existing analytical platforms can be expected to be ideal for exhaustive chemical profiling. Planar liquid chromatography, and in particular, high performance thin layer chromatography (HPTLC), has been used for chemical profiling of natural products in conjunction with metabolomics. HPTLC has specific advantages which include its ability to generate reliable chemical fingerprinting data and facilitate preparative work for metabolite isolation during later stages of metabolomics analysis. In this study, we investigated the chemical profiles of four commercially available basil cultivars, namely Dolly, Emily, Keira, and Rosie. We used HPTLC as the primary analytical tool for the separation of basil cultivars based on detected metabolites, and then compared the results with those obtained with other analytical platforms. We identified the characteristic marker compounds of each basil cultivar from the HPTLC plates and validated their potential using LC-MS and GC-MS analyses as a metabolomics tool. Firstly, we compared the HPTLC data of the four cultivars, obtained with two systems that used silica gel 60 and two mobile phases composed of toluene-EtOAc (8:2, v/v) and EtOAc-formic acid-acetic acid-water (100:11:11:27, v/v), with 1H NMR data to evaluate their separation power. Despite providing lower resolution and detecting fewer compounds, the HPTLC separation power was comparable, and in some cases even better than that of 1H NMR. Additionally, we investigated the potential of HPTLC as a tool for chemical fingerprinting and demonstrated its suitability for preparative purposes that are essential for identifying metabolites in mixture analysis. Metabolites were easily isolated from sample mixtures, and identified with the assistance of GC-MS, LC-MS, and TLC-densitometry.. Several marker compounds were thus identified, including 2,4 di-tertbutylphenol, palmitic acid, hexadecanamide, 9-octadecenamide, squalene, hentriacontane, methyl 3-(3,5-ditert­butyl­4-hydroxyphenyl)propanoic acid, sagerinic acid, and cyanidin-3-O-sophoroside.


Ocimum basilicum , Chromatography, Thin Layer/methods , Mass Spectrometry , Gas Chromatography-Mass Spectrometry , Magnetic Resonance Spectroscopy
3.
Cureus ; 15(6): e40027, 2023 Jun.
Article En | MEDLINE | ID: mdl-37425551

Introduction Coronavirus Disease-2019 (COVID-19) causes olfactory loss one of the initial diagnostic criteria. The brief smell identification test (BSIT) is an objective test frequently used in olfactory dysfunction. This study aimed to observe the changes in olfactory functions and clinical features in a short time in COVID-19. Methods In this prospective study involving 64 patients, the BSIT was performed at two different times; at the time of first application and on the 14th day. Demographic features, laboratory findings, body mass index (BMI), blood oxygen saturation values (SpO2), complaints at first admission, fever, follow-up place, and treatment schemes were noted. Results There was a significant difference between the BSIT scores at the first admission and when the polymerase chain reaction (PCR) became negative on the 14th day (p<0.001). Low oxygen saturation values at first admission were associated with low BSIT scores. No relationship was found between olfactory functions and complaints at admission, fever, follow-up place, and treatment schemes. Conclusion As a result, negative effects of COVID-19 on olfactory functions have been demonstrated even in the short follow-up period. In addition, low saturation values at first admission were associated with low BSIT scores.

5.
Curr Eye Res ; 48(7): 683-689, 2023 07.
Article En | MEDLINE | ID: mdl-37024478

PURPOSE: To determine the loss of follow-up ratio and reasons during the COVID-19 lockdown in patients with retinal diseases treated by anti-vascular endothelial growth factor intravitreal injections and to report the visual outcome and rate of complications of these patients 1 year after the end of the lockdown. METHODS: This is a prospective descriptive cohort study (NCT04395859) conducted at the Rothschild Foundation Hospital - Paris between April 2020 and May 2021. Patients with retinal diseases treated by repeated intravitreal anti-VEGF injections (IVI) since before October 2019 were included. They filled-out a questionnaire and were followed up during a period of 1 year. RESULTS: During the COVID-19 lockdown 198 eyes (82.5%) of 157 patients (82.6%) received their injections in a timely manner (group 1) while 42 eyes (17.5%) of 33 patients (17.4%) had their injections delayed or missed (group 2). No statistically significant difference was found between group 1 and group 2 when comparing the change of mean best corrected distance visual acuity (BCVA) between month 12 and inclusion (p = 0.6) and the rate of ocular complications. The most frequent reasons for missing scheduled injections are appointments cancellation by the hospital (12 patients, 36%), fear of virus exposure during transportation (7 patients, 21%) or at the hospital (5 patients, 15%). Eighty-four percent (130/157 patients) of patients who attended their appointment were satisfied by the protective measures used in the hospital. CONCLUSION: COVID-19 lockdown did not seem to negatively affect the 1-year outcome of patients with retinal diseases treated by anti-VEGF IVIs who missed their scheduled injections. The BCVA and rate of complications at 1 year did not differ whether patients missed their scheduled injections or not. Maintaining IVIs during lockdown periods and educating patients about the risks of missing injections are pivotal in improving prognosis of retinal diseases.


COVID-19 , Macular Edema , Retinal Diseases , Humans , Vascular Endothelial Growth Factor A/therapeutic use , Intravitreal Injections , Macular Edema/drug therapy , Cohort Studies , COVID-19/epidemiology , COVID-19/complications , Communicable Disease Control , Vascular Endothelial Growth Factors , Retinal Diseases/drug therapy , Retinal Diseases/epidemiology , Retinal Diseases/complications , Angiogenesis Inhibitors/therapeutic use , Treatment Outcome , Ranibizumab/therapeutic use , Retrospective Studies , Follow-Up Studies
6.
J Food Sci Technol ; 59(7): 2884-2893, 2022 Jul.
Article En | MEDLINE | ID: mdl-35734123

This study evaluated the antibiotic resistance characteristics and virulence genes of enterococci isolated from raw and processed seafood sold in the Marmara Region, Turkey. In this context, the enterococcal load was determined as between 1.0 and 2.5 log CFU/g in 39 of a total of 397 samples. It was determined that 117 strains isolated from the samples belonged to Enterococcus gallinarum, E. casseliflavus, E. durans, E. faecium, and E. faecalis species. Erythromycin, tetracycline, streptomycin, and gentamicin resistance was observed, whereas the tetM, ermB, aac(6')-aph(2'')-la genes were found in a majority of the isolates. It was also determined that the isolates carried the agg2 and gelE virulence genes. When all these results are evaluated, the presence of these isolates in aquatic products may pose a risk in terms of food safety and public health.

7.
J Phys Act Health ; 18(11): 1358-1363, 2021 09 21.
Article En | MEDLINE | ID: mdl-34548418

BACKGROUND: During the COVID-19 pandemic, restrictive measures can reduce physical activity. The purpose of this study was to evaluate predisease physical activity and current functional capacity in patients with and without the presence of pneumonia and oxygen requirement in Turkish survivors of COVID-19. METHODS: Among the COVID-19 patients admitted to the hospital, 100 patients were selected. Data about predisease physical activity (by short-form International Physical Activity Questionnaire), oxygen requirement and presence of pneumonia, and current functional capacity (by the 6-min walking test) were collected. Continuous and categorical variables were compared with the Mann-Whitney U and χ2 test, respectively (P < .05). RESULTS: The predisease physical activity levels and current functional capacity of patients with pneumonia and oxygen requirement were significantly lower than patients without pneumonia and oxygen requirement (P < .05). However, there was no significant difference between males and females (P > 0.05). Pneumonia and oxygen requirement was more common in the older adults (P < .05). Also, a significant correlation was found between age with predisease physical activity (r = .530, P = .000) and current functional capacity (r = -.346, P = .000) and predisease physical activity level with current functional capacity (r = .523, P = .001). CONCLUSION: The physical activity level may be related to the severity of COVID-19 disease.


COVID-19 , Pneumonia , Aged , Exercise , Female , Humans , Male , Oxygen , Pandemics , Pneumonia/epidemiology , SARS-CoV-2
8.
Metabolites ; 11(3)2021 Mar 17.
Article En | MEDLINE | ID: mdl-33802951

Fungal endophytes isolated from two latex bearing species were chosen as models to show their potential to expand their host plant chemical diversity. Thirty-three strains were isolated from Alstonia scholaris (Apocynaceae) and Euphorbia myrsinites (Euphorbiaceae). High performance thin layer chromatography (HPTLC) was used to metabolically profile samples. The selected strains were well clustered in three major groups by hierarchical clustering analysis (HCA) of the HPTLC data, and the chemical profiles were strongly correlated with the strains' colony size. This correlation was confirmed by orthogonal partial least squares (OPLS) modeling using colony size as "Y" variable. Based on the multivariate data analysis of the HPTLC data, the fastest growing strains of each cluster were selected and used for subsequent experiments: co-culturing to investigate interactions between endophytes-phytopathogens, and biotransformation of plant metabolites by endophytes. The strains exhibited a high capacity to fight against fungal pathogens. Moreover, there was an increase in the antifungal activity after being fed with host-plant metabolites. These results suggest that endophytes play a role in plant defense mechanisms either directly or by biotransformation/induction of metabolites. Regarding HPTLC-based metabolomics, it has proved to be a robust approach to monitor the interactions among fungal endophytes, the host plant and potential phytopathogens.

9.
ACS Omega ; 5(21): 12398-12408, 2020 Jun 02.
Article En | MEDLINE | ID: mdl-32548424

Despite their high therapeutic potential, only a limited number of approved drugs originate from marine natural products. A possible reason for this is their broad metabolic variability related to the environment, which can cause reproducibility issues. Consequently, a further understanding of environmental factors influencing the production of metabolites is required. Giant barrel sponges, Xestospongia spp., are a source of many new compounds and are found in a broad geographical range. In this study, the relationship between the metabolome and the geographical location of sponges within the genus Xestospongia spp. was investigated. One hundred and thirty-nine specimens of giant barrel sponges (Xestospongia spp.) collected in four locations, Martinique, Curaçao, Taiwan, and Tanzania, were studied using a multiplatform metabolomics methodology (nuclear magnetic resonance spectroscopy and liquid chromatography-mass spectrometry). A clear grouping of the collected samples according to their location was shown. Metabolomics analysis revealed that sterols and various fatty acids, including polyoxygenated and brominated derivatives, were related to the differences in locations. To explore the relationship between observed metabolic changes and their bioactivity, antibacterial activity was assessed against Escherichia coli and Staphylococcus aureus. The activity was found to correlate with brominated fatty acids. These were isolated and identified as (9E,17E)-18-bromooctadeca-9,17-dien-5,7,15-triynoic acid (1), xestospongic acid (2), (7E,13E,15Z)-14,16-dibromohexadeca-7,13,15-trien-5-ynoic acid (3), and two previously unreported compounds.

10.
ACS Appl Mater Interfaces ; 10(1): 308-317, 2018 Jan 10.
Article En | MEDLINE | ID: mdl-29232108

Peripheral nerve injuries cause devastating problems for the quality of patients' lives, and regeneration following damage to the peripheral nervous system is limited depending on the degree of the damage. Use of nanobiomaterials can provide therapeutic approaches for the treatment of peripheral nerve injuries. Electroactive biomaterials, in particular, can provide a promising cure for the regeneration of nerve defects. Here, a supramolecular electroactive nanosystem with tetra(aniline) (TA)-containing peptide nanofibers was developed and utilized for nerve regeneration. Self-assembled TA-conjugated peptide nanofibers demonstrated electroactive behavior. The electroactive self-assembled peptide nanofibers formed a well-defined three-dimensional nanofiber network mimicking the extracellular matrix of the neuronal cells. Neurite outgrowth was improved on the electroactive TA nanofiber gels. The neural differentiation of PC-12 cells was more advanced on electroactive peptide nanofiber gels, and these biomaterials are promising for further use in therapeutic neural regeneration applications.


Nanofibers , Aniline Compounds , Animals , Biocompatible Materials , Cell Differentiation , Nerve Regeneration , PC12 Cells , Peptides , Rats
11.
Nanomedicine ; 14(7): 2433-2454, 2018 10.
Article En | MEDLINE | ID: mdl-28552644

One-dimensional (1D) carbon nanotubes (CNTs) and the two-dimensional (2D) graphene represent the most widely studied allotropes of carbon. Due to their unique structural, electrical, mechanical and optical properties, 1D and 2D carbon nanostructures are considered to be leading candidates for numerous applications in biomedical fields, including tissue engineering, drug delivery, bioimaging and biosensors. The biocompatibility and toxicity issues associated with these nanostructures have been a critical impediment for their use in biomedical applications. In this review, we present an overview of the various materials types, properties, functionalization strategies and characterization methods of 1D and 2D carbon nanomaterials and their derivatives in terms of their biomedical applications. In addition, we discuss various factors and mechanisms affecting their toxicity and biocompatibility.


Biosensing Techniques , Drug Delivery Systems , Nanostructures/chemistry , Nanotubes, Carbon/chemistry , Tissue Engineering , Animals , Humans
12.
J Clin Diagn Res ; 11(6): OD11-OD12, 2017 Jun.
Article En | MEDLINE | ID: mdl-28764228

Idiopathic Brachial Neuritis (IBN), is a rare brachial plexopathy with an unknown aetiology. Multiple myeloma is a neoplastic plasma cell disease characterised by bone lesions. In this article, we present the case of a 59-year-old male patient with IBN associated with multiple myeloma, who was admitted to our clinic with right shoulder pain and right arm weakness. He experienced muscle weakness and atrophy in his right arm after a sudden onset of pain attack in the shoulder. Plexus and cervical vertebral MRI showed no pathology. Electrodiagnostic studies showed upper and middle trunk plexopathies. Laboratory analysis revealed anaemia, hypercalcaemia, renal dysfunction and monoclonal gammopathy in immunoglobulin electrophoresis. A bone marrow biopsy established the diagnosis of IgG kappa multiple myeloma. This is the first case report that presents the association of multiple myeloma and IBN.

13.
Arch Rheumatol ; 31(4): 314-320, 2016 Dec.
Article En | MEDLINE | ID: mdl-30375552

OBJECTIVES: This study aims to investigate the effects of aerobic exercise on low density lipoprotein receptor related protein 5 (LRP5) gene messenger ribonucleic acid expression and evaluate the relationship between the clinical parameters and gene expression in patients with postmenopausal osteoporosis (OP). PATIENTS AND METHODS: Seven patients with postmenopausal OP (mean age 60.0±5.3 years; range 51 to 66 years) were included in the study. An exercise protocol/program consisting of treadmill exercising for 30 minutes three days a week for six weeks was performed at a moderate intensity. LRP5 gene expression levels were evaluated before the onset of the exercise program and then four hours after the end of the first session and 12th (fourth week) and 18th (sixth week) sessions of exercise. RESULTS: Our results demonstrated variable changes in the LRP5 gene expression after the aerobic exercise sessions. Excluding one patient, the LRP5 gene expression levels showed a slight tendency to increase. In spite of this tendency, gene expression differences during the exercise sessions were not significant. CONCLUSION: Our results suggest that interindividual variations of LRP5 gene expression exist after moderate intensity aerobic exercises in patients with postmenopausal OP. Despite of this variability, LRP5 gene expression levels increased slightly, except in peripheral blood in one patient. Future studies with larger sample sizes and different sampling time/tissues are required to shed more light on the impact of exercise at molecular level in OP.

14.
Int J Clin Exp Med ; 8(5): 7544-52, 2015.
Article En | MEDLINE | ID: mdl-26221298

PURPOSE: Sacroiliitis based on MRI is one of the main diagnostic criteria of axial spondyloarthritis (SpA). Our purpose was to assess (a) whether apparent diffusion coefficient (ADC) values on diffusion-weighted imaging (DWI) differ between regions of bone marrow edema (BME) and subchondral normal-appearing bone marrow (NABM) in active sacroiliitis, (b) whether ADC values can differentiate early SpA and chronic SpA, both in the active and inactive phase, and (c) whether ADC values are related to laboratory findings. MATERIALS AND METHODS: 47 patients (24 female, 23 male, mean age: 38.53 years) with the diagnosis of SpA were included in this retrospective study. 20 age- and sex-matched subjects without SpA constituted the control group. ADC measurements were taken from all lesions and NABM of each sacroiliac joint. RESULTS: A total number of 120 subchondral BME lesions (acute: 17, chronic active: 103) were noted. The mean ADC values of the BME lesions (1.30 ± 0.18 × 10(-3) mm(2)/s) were significantly higher than the ADC values in the NABM regions (0.55 ± 0.08 × 10(-3) mm(2)/s) as well as in both the control group (0.56 ± 0.05 × 10(-3) mm(2)/s) and the chronic inactive group (0.54 ± 0.03 × 10(-3) mm(2)/s). There were more BME regions in patients with chronic active sacroiliitis than early SpA patients. Correlation was found between the CRP values and ADC values. CONCLUSION: DWI with ADC values may be complementary to FS T2-weighted or STIR MR images for accurately diagnosing inflammatory sacroiliitis. The value of DWI versus dynamic contrast-enhanced imaging in the follow-up needs to be clarified.

15.
Turk J Med Sci ; 44(6): 1047-50, 2014.
Article En | MEDLINE | ID: mdl-25552159

BACKGROUND/AIM: To compare pandemic H1N1 (pH1N1) IgG antibody levels between healthcare workers who were vaccinated with the pH1N1 influenza vaccine and the unvaccinated healthcare workers who were selected as the control group. MATERIALS AND METHODS: A total of 68 healthcare workers were included in this study. Of those, 53 were adults vaccinated with the H1N1 influenza vaccine and 15 were unvaccinated. Serum samples were parsed and stored at -40 °C until they were examined. RESULTS: Of the total 53 vaccinated healthcare workers, 16 (30.1%) were positive for IgG antibodies (titer > 11), 17 (32.0%) were negative for IgG antibodies (titer < 9), and 20 (37.7%) were borderline (titer: 9-11). Of the 15 unvaccinated healthcare workers, 1 (6.6%) was positive for IgG antibodies, 11 (73.3%) were negative for IgG antibodies, and the remaining 3 (20.0%) had borderline values (P = 0.014, P < 0.05). In both groups, there was no statistically significant difference between IgG-negative, IgG-positive, and borderline subjects in terms of age or sex. CONCLUSION: The IgG antibody level was higher in the vaccinated healthcare workers than among the unvaccinated healthcare workers.


Allied Health Personnel/statistics & numerical data , Antibodies, Viral/blood , Immunoglobulin G/blood , Influenza A Virus, H1N1 Subtype/immunology , Influenza, Human/blood , Vaccination/statistics & numerical data , Adult , Female , Humans , Influenza, Human/epidemiology , Influenza, Human/prevention & control , Male , Pandemics , Seroepidemiologic Studies , Turkey/epidemiology
16.
J Colloid Interface Sci ; 392: 75-82, 2013 Feb 15.
Article En | MEDLINE | ID: mdl-23116854

In this work we present an investigation of the influence of particle surface characteristics on the electrorheological (ER) behavior of suspensions of either pure or modified hematite (α-Fe(2)O(3)) particles dispersed in silicone oil. The modification consisted of either dehydration or hydrophobization of the particles before preparing the suspensions. A comparison was performed between the electrorheological responses of suspensions with the same volume fraction of hematite particles having different surface properties. The effects of applied electric field strength on the viscosity, yield stress and dynamic moduli of these suspensions were examined. It was found that the usual positive ER response, that is, enhanced values of the yield stress and elastic modulus induced by the electric field were obtained for hematite and, to a lesser extent, for dried hematite suspensions. In contrast, a "negative ER effect", i.e., the reduction of yield stress and elastic modulus upon application of electric field was observed for hydrophobically modified (oleic acid coated) hematite. This means that the field produces destruction of structures rather than their build up, above a threshold electric field strength.

17.
Article En | MEDLINE | ID: mdl-22988477

Viscum album L. is a semiparasitic plant grown on trees and widely used for the treatment of many diseases in traditional and complementary therapy. It is well known that some activities of Viscum album extracts are varied depending on the host trees, such as antioxidant, apoptosis-inducing, anticancer activities of the plant. The aim of the present study is to examine the comparative effects of methanolic extracts of V. album grown on three different host trees (locust tree, lime tree, and hedge maple tree) on H(2)O(2)-induced DNA damage in HeLa cells. Oxidative damage in mitochondrial DNA and two nuclear regions was assessed by QPCR assay. The cells were pretreated with methanolic extracts (10 µg/mL) for 48 h, followed by the treatment with 750 µM H(2)O(2) for 1 hour. DNA damage was significantly induced by H(2)O(2) while it was inhibited by V. album extracts. All extracts completely protected against nuclear DNA damage. While the extract from lime tree or white locust tree entirely inhibited mitochondrial DNA damage, that from hedge maple tree inhibited by only 50%. These results suggest that methanolic extracts of V. album can prevent oxidative DNA damage, and the activity is dependent on the host tree.

18.
Food Chem Toxicol ; 50(10): 3475-9, 2012 Oct.
Article En | MEDLINE | ID: mdl-22877972

Oxidative DNA damage is an inescapable consequence for cells constantly exposed to oxidative stress derived from normal metabolic processes and from environmental factors. Phenolic compounds, which have strong antioxidant activity, prevent DNA damage by protecting the cells against harmful effects of oxidative stress. In this study, the effect of virgin olive oil phenolic extract (OOPE) was investigated on H2O2-induced mitochondrial DNA (mtDNA) and nuclear DNA (nDNA) damage in HeLa cells. DNA damage was assessed in mitochondria and two nuclear regions by using quantitative PCR (QPCR) assay. The cells were pre-treated with non-cytotoxic doses of OOPE for 4 h, and DNA damage was determined. OOPE alone does not change the steady-state level of DNA damage. The oxidative stress generated with 750 µM H2O2 caused two times greater damages in mtDNA compared to nDNA, which included the nonexpressed ß-globin region (1.507±0.110 lesions/10 kb) and the expressed APEX1 gene (1.623±0.243 lesions/10 kb) with respect to the control region. When cells were preincubated with OOPE for 4 h, nDNA damage under stress condition was completely inhibited; however, mtDNA damage was not affected by this procedure. These results suggest that OOPE has a protective effect against nDNA damage in HeLa cells.


DNA Damage/drug effects , Phenol/pharmacology , Plant Oils/chemistry , HeLa Cells , Humans , Hydrogen Peroxide/metabolism , Kinetics , Olive Oil , Oxidation-Reduction , Phenol/chemistry
19.
Mar Drugs ; 8(9): 2466-79, 2010 Sep 03.
Article En | MEDLINE | ID: mdl-20948900

Three myxobacterial strains, designated SWB004, SWB005 and SWB006, were obtained from beach sand samples from the Pacific Ocean and the North Sea. The strains were cultivated in salt water containing media and subjected to studies to determine their taxonomic status, the presence of genes for the biosynthesis of polyketides and antibiotic production. 16S rDNA sequence analysis revealed the type strain Enhygromyxa salina SHK-1(T) as their closest homolog, displaying between 98% (SWB005) and 99% (SWB004 and SWB006) sequence similarity. All isolates were rod-shaped cells showing gliding motility and fruiting body formation as is known for myxobacteria. They required NaCl for growth, with an optimum concentration of around 2% [w/v]. The G + C-content of genomic DNA ranged from 63.0 to 67.3 mol%. Further, the strains were analyzed for their potential to produce polyketide-type structures. PCR amplified ketosynthase-like gene fragments from all three isolates enhances the assumption that these bacteria produce polyketides. SWB005 was shown to produce metabolites with prominent antibacterial activity, including activity towards methicillin resistant Staphylococcus aureus (MRSA) and Staphylococcus epidermidis (MRSE).


Anti-Bacterial Agents/biosynthesis , Genes, Bacterial , Geologic Sediments/microbiology , Myxococcales/isolation & purification , Myxococcales/physiology , Anti-Bacterial Agents/pharmacology , Base Composition , DNA, Bacterial/analysis , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/genetics , Myxococcales/cytology , Myxococcales/genetics , Phenotype , Phylogeny , Salt Tolerance , Seawater/microbiology , Sequence Analysis, DNA , Sodium Chloride
20.
Chembiochem ; 11(9): 1253-65, 2010 Jun 14.
Article En | MEDLINE | ID: mdl-20503218

Corallopyronin A is a myxobacterial compound with potent antibacterial activity. Feeding experiments with labelled precursors resulted in the deduction of all biosynthetic building blocks for corallopyronin A and revealed an unusual feature of this metabolite: its biosynthesis from two chains, one solely PKS-derived and the other NRPS/PKS-derived. The starter molecule is believed to be carbonic acid or its monomethyl ester. The putative corallopyronin A biosynthetic gene cluster is a trans-AT-type mixed PKS/NRPS gene cluster, containing a beta-branching cassette. Striking features of this gene cluster are a NRPS-like adenylation domain that is part of a PKS-type module and is believed to be responsible for glycine incorporation, as well as split modules with individual domains occurring on different genes. It is suggested that CorB is a trans-acting ketosynthase and it is proposed that it catalyses the Claisen condensation responsible for the interconnection of the two chains. Additionally, the stereochemistry of corallopyronin A was deduced by a combination of a modified Mosher's method and ozonolysis with subsequent chiral GC analyses.


Anti-Bacterial Agents/biosynthesis , Lactones/metabolism , Myxococcales/enzymology , Amino Acid Sequence , Anti-Bacterial Agents/chemistry , Lactones/chemistry , Molecular Sequence Data , Multigene Family , Peptide Synthases/genetics , Peptide Synthases/metabolism , Polyketide Synthases/genetics , Polyketide Synthases/metabolism , Sequence Alignment , Stereoisomerism
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