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Chemistry and Physics of Lipids Mar 2016Dermabacter hominis is a medically important actinobacterial inhabitant of human skin, although it is rarely implicated in infections. The lipid composition of D....
Dermabacter hominis is a medically important actinobacterial inhabitant of human skin, although it is rarely implicated in infections. The lipid composition of D. hominis is revisited in this study in the context of its natural resistance to daptomycin, an antibiotic whose activity is influenced by membrane lipids. Thin layer chromatography and mass spectrometry revealed that this species contains phospholipids and glycolipids. Using electrospray ionization time of flight mass spectrometry (exact mass) and gas chromatography-mass spectrometry, the major phospholipid of D. hominis was identified as plasmanyl-phosphatidylglycerol (pPG), because it presented one alkyl chain and one acyl chain in the glycerol moiety of the molecule. The structure of the major glycolipid (GL1) was studied by combined gas-liquid chromatography, mass spectrometry and nuclear magnetic resonance, and was established as galactosyl-α-(1→2)-glucosyl-alkyl-acyl-glycerol. Lipid analyses showed differences between one daptomycin-resistant (DAP-R) strain and one daptomycin-sensitive (DAP-S) strain growing in the presence of the antibiotic: DAP-R tended to accumulate GL1 and to reduce pPG, whereas DAP-S maintained high proportions of pPG. The results demonstrate the existence of ether-linked lipids in D. hominis and reveal a differential distribution of phospholipids and glycolipids according to the sensitivity or resistance to daptomycin, although the mechanism(s) operating in the resistance to the antibiotic remain(s) to be elucidated.
Topics: Actinobacteria; Ethers; Humans; Lipids; Skin; Spectrometry, Mass, Electrospray Ionization
PubMed: 26867985
DOI: 10.1016/j.chemphyslip.2016.02.002 -
International Journal of Systematic and... Apr 2016A novel actinobacterial strain, AD1-86T, was isolated from the vaginal fluid of a Korean female and was characterized by a polyphasic approach. The strain was a...
A novel actinobacterial strain, AD1-86T, was isolated from the vaginal fluid of a Korean female and was characterized by a polyphasic approach. The strain was a facultatively anaerobic, Gram-stain-positive, non-spore-forming, non-motile, catalase-positive and oxidase-negative short rod. Colonies were creamy white, of low convexity and 1-2 mm in diameter after growth on DSM 92 agar plates at 37 °C for 2 days. The most closely related strains were Dermabacter hominis DSM 7083T and Helcobacillus massiliensis 6401990T (98.3 and 96.3 % 16S rRNA gene sequence similarity, respectively). The isolate grew optimally at 37 °C and pH 7 in the presence of 0.5% (w/v) NaCl. The cell-wall peptidoglycan contained meso-diaminopimelic acid and the cell-wall hydrolysates contained ribose, galactose and glucose. The DNA G+C content was 62.6 mol% and the mean DNA-DNA relatedness value of the isolate to D. hominis DSM 7083T was 31.1±3.0% (reciprocal: 48.2±5.3%). The major cellular fatty acids (>10%) were anteiso-C17:0, anteiso-C15:0 and iso-C16:0, and the menaquinones were MK-9, MK-8 and MK-7. The polar lipid profile of strain AD1-86T consisted of diphosphatidylglycerol, phosphatidylglycerol, two aminolipids and a glycolipid. Data from this polyphasic study indicate that strain AD1-86T represents a novel species of the genus Dermabacter, for which the name Dermabacter vaginalis sp. nov. is proposed; the type strain is AD1-86T (=KCTC 39585T=DSM 100050T).
Topics: Actinomycetales; Asian People; Bacterial Typing Techniques; Base Composition; DNA, Bacterial; Diaminopimelic Acid; Fatty Acids; Female; Glycolipids; Humans; Molecular Sequence Data; Nucleic Acid Hybridization; Peptidoglycan; Phospholipids; Phylogeny; RNA, Ribosomal, 16S; Republic of Korea; Sequence Analysis, DNA; Vagina; Vitamin K 2
PubMed: 26867728
DOI: 10.1099/ijsem.0.000960 -
International Journal of Infectious... Jun 2015Breast implant infections are usually caused by Staphylococcus aureus and coagulase-negative staphylococci. Gram-negative bacilli are rarely reported to be involved in...
BACKGROUND
Breast implant infections are usually caused by Staphylococcus aureus and coagulase-negative staphylococci. Gram-negative bacilli are rarely reported to be involved in breast implant infections.
METHODS
Thirty-seven cases of microbiologically confirmed breast implant infection managed from January 2008 to June 2012 in the study centre were reviewed, including 10 cases from the study centre itself and 27 cases from private clinics in the region.
RESULTS
The prevalence of breast implant infection in the study centre was 0.74% of breast implantation, i.e., 3.23% in breast reconstruction for breast cancer and 0.27% in aesthetic breast augmentation (p=0.0002). Of the 37 cases, 30% had undergone radiotherapy and 11% had undergone a lymph node dissection. S. aureus was identified in 18 cases, Gram-negative bacilli in 10 cases, coagulase-negative staphylococci in eight cases, anaerobic bacteria in eight cases, and streptococci in three cases. Pseudomonas aeruginosa was the second most commonly identified pathogen. Staphylococcus epidermidis was the most frequent coagulase-negative Staphylococcus species. In addition to Propionibacterium acnes and Actinomyces neuii, other facultative and strict anaerobic bacteria have not been reported before, e.g., Bacteroides thetaiotaomicron, Corynebacterium simulans, Dermabacter hominis, Finegoldia magna, and Peptoniphilus harei. Seventy-percent of cases were treated by immediate implant removal. All cases treated only with antibiotics were treated with surgery at the second visit.
CONCLUSIONS
The microbiological epidemiology was noted by an increasing the proportion of Gram-negative bacteria and anaerobic bacteria detected with the advent of MALDI-TOF MS and molecular identification for diagnosis.
Topics: Adult; Aged; Bacteria; Bacterial Infections; Breast Diseases; Breast Implants; Female; France; Gram-Negative Bacteria; Humans; Mammaplasty; Middle Aged; Postoperative Complications; Pseudomonas aeruginosa; Referral and Consultation; Staphylococcus; Staphylococcus aureus; Young Adult
PubMed: 25910855
DOI: 10.1016/j.ijid.2015.04.010 -
New Microbes and New Infections Dec 2013During a 12-year period, Dermabacter hominis was isolated from 21 clinical samples belonging to 14 patients attending a tertiary hospital in León, Spain. Samples...
During a 12-year period, Dermabacter hominis was isolated from 21 clinical samples belonging to 14 patients attending a tertiary hospital in León, Spain. Samples included blood cultures (14), peritoneal dialysis catheter exit sites (three), cutaneous abscesses (two), an infected vascular catheter (one) and a wound swab (one). Identification was made by API Coryne™ V2.0, Biolog™ GP2 and 16S rRNA gene amplification. Six febrile patients had positive blood cultures (one, two or three sets) and all of them were treated with teicoplanin (two patients), vancomycin, ampicillin plus gentamicin, amoxicillin/clavulanic acid and ciprofloxacin (one each). An additional patient with a single positive blood culture was not treated, the finding being considered non-significant. In the remaining seven patients the organism was isolated from a single specimen and three of them received antimicrobial treatment (ciprofloxacin, ceftriaxone plus vancomycin and amoxicillin/clavulanic acid). At least ten patients had several underlying diseases and conditions, and no direct mortality was observed in relation to the isolated organism. All isolates were susceptible to vancomycin, rifampin and linezolid. Resistance to other antibiotics varied: erythromycin (100%), clindamycin (78.5%), ciprofloxacin (21.4%) and gentamicin, quinupristin-dalfopristin, benzylpenicillin and imipenem 7.1% each. Thirteen isolates were highly resistant to daptomycin with MICs ranging from 8 to 48 (MIC90 = 32 mg/L); only one was daptomycin-sensitive (MIC = 0.19 mg/L).
PubMed: 25356327
DOI: 10.1002/2052-2975.31 -
Changes in gastric and lung microflora with acid suppression: acid suppression and bacterial growth.JAMA Pediatrics Oct 2014The use of acid suppression has been associated with an increased risk of upper and lower respiratory tract infections in the outpatient setting but the mechanism behind...
IMPORTANCE
The use of acid suppression has been associated with an increased risk of upper and lower respiratory tract infections in the outpatient setting but the mechanism behind this increased risk is unknown. We hypothesize that this infection risk results from gastric bacterial overgrowth with subsequent seeding of the lungs.
OBJECTIVES
To determine if acid-suppression use results in gastric bacterial overgrowth, if there are changes in lung microflora associated with the use of acid suppression, and if changes in lung microflora are related to full-column nonacid gastroesophageal reflux.
DESIGN, SETTING, AND PARTICIPANTS
A 5-year prospective cohort study at a tertiary care center where children ages 1 to 18 years were undergoing bronchoscopy and endoscopy for the evaluation of chronic cough. Acid-suppression use was assessed through questionnaires with confirmation using an electronic medical record review.
MAIN OUTCOMES AND MEASURES
Our primary outcome was to compare differences in concentration and prevalence of gastric and lung bacteria between patients who were and were not receiving acid-suppression therapy. We compared medians using the Wilcoxon signed rank test and determined prevalence ratios using asymptotic standard errors and 95% confidence intervals. We determined correlations between continuous variables using Pearson correlation coefficients and compared categorical variables using the Fisher exact test.
RESULTS
Forty-six percent of patients taking acid-suppression medication had gastric bacterial growth compared with 18% of untreated patients (P = .003). Staphylococcus (prevalence ratio, 12.75 [95% CI, 1.72-94.36]), Streptococcus (prevalence ratio, 6.91 [95% CI, 1.64-29.02]), Veillonella (prevalence ratio, 9.56 [95% CI, 1.26-72.67]), Dermabacter (prevalence ratio, 4.78 [95% CI, 1.09-21.02]), and Rothia (prevalence ratio, 6.38 [95% CI, 1.50-27.02]) were found more commonly in the gastric fluid of treated patients. The median bacterial concentration was higher in treated patients than in untreated patients (P = .001). There was no difference in the prevalence (P > .23) of different bacterial genera or the median concentration of total bacteria (P = .85) in the lungs between treated and untreated patients. There were significant positive correlations between proximal nonacid reflux burden and lung concentrations of Bacillus (r = 0.47, P = .005), Dermabacter (r = 0.37, P = .008), Lactobacillus (r = 0.45, P = .001), Peptostreptococcus (r = 0.37, P = .008), and Capnocytophagia (r = 0.37, P = .008).
CONCLUSIONS AND RELEVANCE
Acid-suppression use results in gastric bacterial overgrowth of genera including Staphylococcus and Streptococcus. Full-column nonacid reflux is associated with greater concentrations of bacteria in the lung. Additional studies are needed to determine if acid suppression-related microflora changes predict clinical infection risk; these results suggest that acid suppression use may need to be limited in patients at risk for infections.
Topics: Adolescent; Antacids; Bacterial Infections; Child; Child, Preschool; Female; Gastroesophageal Reflux; Humans; Hydrogen-Ion Concentration; Infant; Lung; Lung Diseases; Male; Prospective Studies; Stomach; Stomach Diseases
PubMed: 25133779
DOI: 10.1001/jamapediatrics.2014.696 -
Genome Announcements Jul 2014Dermabacter hominis is a common colonizer of the healthy human skin and is rarely detected as an opportunistic human pathogen. The genome sequence of the...
Dermabacter hominis is a common colonizer of the healthy human skin and is rarely detected as an opportunistic human pathogen. The genome sequence of the multidrug-resistant D. hominis strain 1368, isolated from blood cultures of a pyelonephritis patient, provides insights into the repertoire of antibiotic resistance genes.
PubMed: 25059872
DOI: 10.1128/genomeA.00728-14 -
Microbial Ecology in Health and Disease 2014Coryneform bacteria constitute an important segment of male urogenital microbiota. They have been generally considered as saprophytes, although some species have been...
BACKGROUND
Coryneform bacteria constitute an important segment of male urogenital microbiota. They have been generally considered as saprophytes, although some species have been associated with prostatitis as well. At the same time, biofilm infections have been suspected as a cause of prostatitis.
OBJECTIVE
To identify a set of coryneform bacteria isolated from semen of either healthy men or prostatitis patients applying different methods to reveal inter-assay variability and to determine their ability of adhesion and biofilm production.
DESIGN
Coryneform bacteria were identified by API Coryne 2.0 biochemical identification system and 16S rDNA sequencing using different primer sets. Quantitative assessment of biofilm production was performed using crystal violet binding assay method.
RESULTS
The most common species were Corynebacterium seminale, C. minutissimum, and Dermabacter hominis. Altogether 14 species and related genera were found. We observed the best inter-assay agreement when identifying C. seminale. Biofilm was observed in 7 out of 24 strains. The biofilm-producing strains belonged to Arthrobacter cumminsii, Dermabacter hominis, C. minutissimum, and Actinomyces neuii. No differences were found between the strains originating from prostatitis patients and healthy men. Dermabacter hominis strains were more potent biofilm producers than C. seminale strains (p=0.048).
CONCLUSIONS
We can conclude that a wide variety of coryneform bacteria can be found from the male genital tract, although their exact identification is problematic due to insufficient representation in databases. Nearly one third of the strains are able to form biofilm that may give them an advantage for surviving several host- and treatment-related conditions.
PubMed: 24563649
DOI: 10.3402/mehd.v25.22701 -
International Journal of Systematic and... Sep 2009Gram-positive, non-spore-forming rods (strain 6401990T), isolated from a human cutaneous discharge were subjected to a polyphasic taxonomy study. The only respiratory...
Gram-positive, non-spore-forming rods (strain 6401990T), isolated from a human cutaneous discharge were subjected to a polyphasic taxonomy study. The only respiratory quinone was MK-7 and the major fatty acids were anteiso-C15:0 (34.3%), anteiso-C17:0 (18.7%) and iso-C16:0 (18.6%). Mycolic acids were not present. Polar lipids present were phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine and unidentified glycolipids. The isomer of diaminopimelic acid identified was meso-diaminopimelic acid, and the analysis of whole-cell sugars showed the presence of high amounts of galactose, ribose and some glucose. The G+C content of strain 6401990T was 68.6%. Phylogenetic analysis based on 16S rRNA gene sequence comparisons showed 95.1% similarity with Dermabacter hominis. On the basis of phenotypic data and phylogenetic inference, it is proposed that this strain represents a novel species in a new genus of the family Dermabacteraceae, for which the name Helcobacillus massiliensis gen. nov., sp. nov. is proposed. The type strain is 6401990T (CSUR P17T=CIP 109418T=CCUG 53859T).
Topics: Actinomycetales; Bacterial Typing Techniques; Base Composition; Cluster Analysis; DNA, Bacterial; DNA, Ribosomal; Diaminopimelic Acid; Fatty Acids; Galactose; Glucose; Glycolipids; Humans; Molecular Sequence Data; Mycolic Acids; Phospholipids; Phylogeny; Quinones; RNA, Ribosomal, 16S; Ribose; Sequence Analysis, DNA; Skin Diseases, Bacterial
PubMed: 19620359
DOI: 10.1099/ijs.0.003319-0 -
Anaerobe Oct 2009A case of recurrent abscesses in an immunocompetent patient is reported, involving the opportunistic human pathogen Dermabacter hominis, the virulent anaerobic pathogen...
A case of recurrent abscesses in an immunocompetent patient is reported, involving the opportunistic human pathogen Dermabacter hominis, the virulent anaerobic pathogen Finegoldia magna and Staphylococcus aureus.
Topics: Abscess; Actinomycetales; Adult; Gram-Positive Bacteria; Gram-Positive Bacterial Infections; Humans; Male; Recurrence; Staphylococcus aureus
PubMed: 19332143
DOI: 10.1016/j.anaerobe.2009.03.006 -
International Journal of Systematic and... Sep 2008Five bacterial isolates were recovered from dermatitis or organ lesions of five agamid lizards. Three strains were recovered from Uromastyx species with dermatitis or...
Five bacterial isolates were recovered from dermatitis or organ lesions of five agamid lizards. Three strains were recovered from Uromastyx species with dermatitis or septicaemia. All five isolates were Gram-positive small rods that could not be identified using conventional phenotypic systems. They grew on sheep blood agar as small haemolytic colonies after 24 h of incubation at temperatures between 25 and 42 degrees C under aerobic, microaerophilic or anaerobic conditions. They were catalase-positive and non-motile. Comparative analysis of 16S rRNA gene sequences revealed that the strains represent a new taxon within the class Actinobacteria. Their nearest phylogenetic neighbours were determined as Brachybacterium faecium LMG 19847(T) (95.9% 16S rRNA gene sequence similarity) and Dermabacter hominis NCIMB 13131(T) (95.3% similarity). The DNA G+C content of one of the novel isolates, strain IMP2(T), was 61 mol%. On the basis of morphological, chemotaxonomic and phylogenetic differences from other species of coryneform bacteria, it is proposed that this novel taxon be classified as Devriesea agamarum gen. nov., sp. nov. The type strain is IMP2(T) (=LMG 24257(T)=CCUG 55056(T)).
Topics: Actinomycetales; Aerobiosis; Animals; Base Composition; Catalase; DNA, Bacterial; DNA, Ribosomal; Dermatitis; Fatty Acids; Genes, rRNA; Lizards; Locomotion; Molecular Sequence Data; Phylogeny; RNA, Bacterial; RNA, Ribosomal, 16S; Sepsis; Sequence Analysis, DNA; Sequence Homology, Nucleic Acid; Temperature; Vitamin K 2
PubMed: 18768630
DOI: 10.1099/ijs.0.65478-0