Nesterenkonia haasae sp. nov., an alkaliphilic actinobacterium isolated from a degraded pasture in Songnen Plain.

An alkaliphilic actinobacterial strain, designated Hz 6-5T, was isolated from saline-alkaline soil from Songnen Plain in north-eastern China. The isolate formed light yellow-colored colonies and its cells were Gram-staining positive, non-motile, and non-spore-forming short rods. The strain was aerobic with optimal growth at 33 °C, pH 9.0, and in the presence of 0.5% (w/v) NaCl or 3% (w/v) KCl. It was catalase-positive and oxidase-negative. The isolate had highest 16S rRNA gene sequence similarities to the type strains of the species Nesternkonia natronophila M8T (98.2%), N. salmonea GY074T (98.1%), and N. sphaerica GY239T (97.4%), and the isolate formed a subclade with the type strains of these species in the neighbor-joining tree based on the 16S rRNA gene sequences. The phylogenetic tree based on the phylogenomic analysis also showed the same results. The DNA‒DNA relatedness (DDH) values of isolate Hz 6-5T with N. natronophila M8T, N. halophila DSM 16378T, and N. halobia CGMCC 1.2323T were 21.2%, 36.5%, and 32.0%, respectively. The characteristic diamino acid of strain Hz 6-5T was found to be lysine. The respiratory quinones were MK-9, MK-8, MK-7(H4), MK-7(H2) and MK-7 and the major cellular fatty acids (> 10%) were anteiso-C15:0, anteiso-C17:0 and iso-C16:0. The polar lipids detected for strain Hz 6-5T were diphosphatidylglycerol, phosphatidylcholine, phosphatidylglycerol, phosphatidylinositol, an unidentified glycolipid, and two unidentified phospholipids. The DNA G + C content of isolate Hz 6-5T was 60.8%. Based on the results of phylogenetic analysis supported by morphological, physiological, chemotaxonomic, and other differentiating phenotypic evidence, strain Hz 6-5T is considered to represent a novel species of the genus Nesterenkonia, for which the name Nesterenkonia haasae sp. nov. is proposed. The type strain is Hz 6-5T (=CPCC 205100T=NBRC 113521T).

Rothia spp. infective endocarditis: A systematic literature review.

OBJECTIVE: To describe the epidemiological, clinical, microbiological, and therapeutic features and outcomes of Rothia infective endocarditis (RIE) and extracardiac infections (ECRI). METHODS: We performed a systematic literature review of published cases of RIE and ECRI. RESULTS: After inclusion of a personal case report, 51 cases of RIE and 215 cases of ECRI were reported. Compared with ECRI patients, RIE patients were significantly more often males (80% versus 59%), intravenous drug users (IVDU) (20% versus 3%), immunocompetent (76% versus 31%), and infected with R. dentocariosa (55% versus 13%) but lacked significant differences with regard to median age (45 years [6-79]), rate of orodental abnormalities (33%), and six-month mortality (14%). Following microbiological documentation, RIE was most often treated with a beta-lactam antibiotic alone (39%) for a median duration of six weeks and required surgery in 39% of cases. CONCLUSION: RIE is rare and likely secondary to a dental portal of entry or cutaneous inoculation in IVDU. Its prognosis seems to be favorable.

Longitudinal metabolic and gut bacterial profiling of pregnant women with previous bariatric surgery.

OBJECTIVE: Due to the global increase in obesity rates and success of bariatric surgery in weight reduction, an increasing number of women now present pregnant with a previous bariatric procedure. This study investigates the extent of bariatric-associated metabolic and gut microbial alterations during pregnancy and their impact on fetal development. DESIGN: A parallel metabonomic (molecular phenotyping based on proton nuclear magnetic resonance spectroscopy) and gut bacterial (16S ribosomal RNA gene amplicon sequencing) profiling approach was used to determine maternal longitudinal phenotypes associated with malabsorptive/mixed (n=25) or restrictive (n=16) procedures, compared with women with similar early pregnancy body mass index but without bariatric surgery (n=70). Metabolic profiles of offspring at birth were also analysed. RESULTS: Previous malabsorptive, but not restrictive, procedures induced significant changes in maternal metabolic pathways involving branched-chain and aromatic amino acids with decreased circulation of leucine, isoleucine and isobutyrate, increased excretion of microbial-associated metabolites of protein putrefaction (phenylacetlyglutamine, p-cresol sulfate, indoxyl sulfate and p-hydroxyphenylacetate), and a shift in the gut microbiota. The urinary concentration of phenylacetylglutamine was significantly elevated in malabsorptive patients relative to controls (p=0.001) and was also elevated in urine of neonates born from these mothers (p=0.021). Furthermore, the maternal metabolic changes induced by malabsorptive surgery were associated with reduced maternal insulin resistance and fetal/birth weight. CONCLUSION: Metabolism is altered in pregnant women with a previous malabsorptive bariatric surgery. These alterations may be beneficial for maternal outcomes, but the effect of elevated levels of phenolic and indolic compounds on fetal and infant health should be investigated further.

Nesterenkonia salmonea sp. nov. and Nesterenkonia sphaerica sp. nov., isolated from the Southern Atlantic Ocean.

Two Gram-positive, aerobic, non-motile and non-spore-forming actinobacteria, strains GY074T and GY239T, were isolated from deep-sea sediment of the Southern Atlantic Ocean. The results of phylogenetic analysis of 16S rRNA gene sequences placed both isolates within the genus Nesterenkonia, and showed a sequence similarity of 98.3 % between the two strains and similarites of 94.3-97.2 % with respect to Nesterenkonia species with validly published names. Based on whole-genome sequences, the values of in silico DNA-DNA hybridization and the average nucleotide identity between strains GY074T and GY239T were 21.2 and 78.1 %, respectively, less than the proposed cut-off level for species delineation, i.e. 70 and 95 %. For both strains, the major cellular fatty acids were anteiso-C17 : 0 and anteiso-C15 : 0, and the major menaquinones were MK-7, MK-8 and MK-9. The major polar lipid contents of the two strains were similar with phosphatidylinositol, phosphatidylglycerol, diphosphatidylglycerol and an unidentified glycolipid. The genomic DNA G+C contents of strains GY074T and GY239T were 61.1 and 64.2 mol%, respectively. On the basis of the phylogenetic analysis and physiological and chemotaxonomic data, the isolates represent two novel species of the genus Nesterenkonia, for which the names Nesterenkonia salmonea sp. nov. (type strain GY074T=KCTC 39639T=MCCC 1A11256T) and Nesterenkonia sphaerica sp. nov. (type strain GY239T=KCTC 39640T=MCCC 1A10688T) are proposed.

Kocuria coralli sp. nov., a novel actinobacterium isolated from coral reef seawater.

An actinobacterial strain, SCSIO 13007T, was isolated from seawater collected from the Luhuitou fringing reef at a depth of 4.2 m. Phylogenetic and phenotypic properties of the organism supported the hypothesis that it represented a member of the genus Kocuria. Phylogenetic analysis indicated that the levels of 16S rRNA gene sequence similarity between SCSIO 13007T and type strains of other recognized members of the genus Kocuria were lower than 96.99 %. Growth in the presence of up to 15 % (w/v) NaCl was a distinctive characteristic of SCSIO 13007T. Other biochemical and physiological properties and the major fatty acids also differentiated the isolate from its phylogenetically closest relative Kocuria subflava YIM 13062T. The menaquinone types were MK-7(H2) and MK-8(H2). Major cellular fatty acids were anteiso-C15 : 0, iso-C15 : 0 and anteiso-C17 : 0. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, an unidentified lipid and an unidentified aminolipid. The DNA G+C content was 73.7 mol%. The combined genotypic and phenotypic data indicated that strain SCSIO 13007T represents a novel species of the genus Kocuria, for which the name Kocuria coralli sp. nov. is proposed; the type strain is SCSIO 13007T (=DSM 27811T=NBRC 109942T).

Half of 'Micrococcus spp.' cases identified by conventional methods are revealed as other life-threatening bacteria with different drug susceptibility patterns by 16S ribosomal RNA gene sequencing.

Bacterial infection during chemotherapy is a fatal complication, therefore precise identification of the pathogenic microorganism is required for treatment. We report that 2 of 4 pediatric patients with malignancy who were diagnosed with Micrococcus spp. infection by conventional methods were finally revealed to have Kytococcus schroeteri and Kocuria marina infection by 16S ribosomal RNA gene sequence analysis (16S rRNA analysis). Although K. schroeteri is morphologically similar to Micrococcus spp., its drug susceptibility profile is quite different from that of Micrococcus spp. K. schroeteri is resistant to penicillin and cephalosporin, which are effective for Micrococcus spp. In fact, penicillin-resistant lethal pneumonia caused by K. schroeteri has been reported in compromised hosts. Based on our results, Micrococcus spp. determined by conventional methods could contain other life-threatening bacteria with different drug susceptibility patterns from Micrococcus spp. To develop an effective empirical treatment for immunocompromised hosts, accumulation of pathogen data by 16S rRNA analysis is required.

Kocuria soli sp. nov., an actinobacterium isolated from soil.

A Gram-stain-positive, aerobic, coccoid-shaped, non-spore-forming actinobacterial strain, designated M5W7-7T, was isolated from a hot spring soil sample collected from Anshan, Liaoning province, PR China. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain M5W7-7T clustered closely with species of the genus Kocuria, and showed the highest sequence similarity of 97.1 % to Kocuria subflava YIM 13062T. Strain M5W7-7T grew at 10-37 °C (optimum, 37 °C), pH6.0-11.0 (pH 6.0-7.0) and in the presence of 0-7 % (w/v) NaCl (0 %). Substrate mycelia and aerial mycelia were not formed, and diffusible pigments were not observed on any media tested. Strain M5W7-7T contained MK-6(H2) and MK-7(H2) as the dominant menaquinones. The polar lipid profile of strain M5W7-7T contained diphosphatidylglycerol, phosphatidylglycerol, two unidentified glycolipids, an unidentified phospholipid and an unidentified lipid. The predominant whole-cell sugars were galactose and glucose. The predominant fatty acid was anteiso-C15 : 0. The DNA G+C content of strain M5W7-7T was 67.0 mol%. On the basis of phylogenetic relationships, phenotypic characterization and chemotaxonomic analyses, strain M5W7-7T represents a novel species of the genus Kocuria, for which the name Kocuriasoli sp. nov. is proposed. The type strain is M5W7-7T (=KCTC 49195T =CGMCC 1.13744T).

Specibacter cremeus gen. nov., sp. nov., a new member of the family Micrococcaceae isolated from a natural cave.

A Gram-reaction-positive, non-spore-forming, rod-shaped bacterium, strain C1-50T, was isolated from a natural cave in Jeju, Republic of Korea by using the serial dilution plating method. Results of phylogenetic analysis using 16S rRNA gene sequences showed that strain C1-50T belonged to the family Micrococcaceae but had the highest sequence similarity to Arthrobacter halodurans JSM 078085T (96.18 %) and Arthrobacter globiformis DSM 20124T (96.04 %). The 16S rRNA gene sequence similarities between strain C1-50T and other members of the family were lower than 96.0 %. The cell-wall peptidoglycan type was A3α with an l-Lys-l-Ala2. Whole-cell sugars consisted largely of glucose and galactose. The predominant menaquinone was MK-9(H2) with smaller components of MK-7(H2) and MK-8(H2). The polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol and an unidentified glycolipid. The cellular fatty acids consisted of saturated, unsaturated, anteiso-branched and iso-branched components. The G+C content of genomic DNA was 68.8 mol% (draft genome sequence). On the basis of morphological and chemotaxonomic differences and distinct phylogenetic clustering, it was concluded that the organism represents a novel species of a new genus in the family Micrococcaceae, for which the name Specibacter cremeus gen. nov., sp. nov. is proposed. The type strain is C1-50T (=KCTC 39557T=DSM 100066T).

Kocuria tytonis sp. nov., isolated from the uropygial gland of an American barn owl (Tyto furcata).

Avian uropygial glands have received increasing attention in recent years, but little is known about micro-organisms in uropygial glands. In this study, we isolated a strain of Gram-stain-positive, non-motile, non-spore-forming cocci, designated 442T, from the uropygial gland of an American barn owl (Tyto furcata) and characterized it using a polyphasic approach. 16S rRNA gene sequence analysis placed the isolate in the genus Kocuria. The G+C content was 70.8 mol%, the major menaquinone was MK-7(H2) and the predominant cellular fatty acids were anteiso-C15 : 0, anteiso-C17 : 0 and iso-C15 : 0. Phylogenetic analyses based on the 16S rRNA gene identified Kocuria rhizophila DSM 11926T (99.6 % similarity), Kocuria salsicia DSM 24776T (98.7 %), Kocuria varians DSM 20033T (98.3 %) and Kocuria marina DSM 16420T (98.3 %) as the most closely related species. However, average nucleotide identity values below 86 % indicated that the isolate differed from all species hitherto described. Chemotaxonomic analyses and whole-cell protein profiles corroborated these findings. Accordingly, the isolate is considered to be a member of a novel species, for which the name Kocuria tytonis sp. nov. is proposed. The type strain is 442T (=DSM 104130T=LMG 29944T).

First case of a bloodstream infection caused by the genus Brachybacterium.

An 83-year-old previously self-sufficient man was referred to our hospital for a fever, severe tenderness over the lumbar spine, and elevated C-reactive protein levels. Computed tomography revealed fluid collection in the intervertebral space of L3/4. Gram-positive, short rod-shaped bacteria were isolated from two sets of blood cultures. A 16S rRNA sequence analysis of an isolate showed a similarity of 98.1% to the nearest type strain Brachybacterium squillarum JCM 16464T. Biochemical characteristics of the presently isolated strain differed from those of the most closely related species of the genus Brachybacterium. The patient was successfully discharged on day 73 of admission with antimicrobial therapies and showed no recurrence during outpatient visits. Brachybacterium spp. have mainly been isolated from the environment, and human Brachybacterium infections have rarely been documented to date. To our knowledge, this is the first clinical isolation of Brachybacterium sp. as a causative pathogen of bloodstream infection.

Kocuria uropygioeca sp. nov. and Kocuria uropygialis sp. nov., isolated from the preen glands of Great Spotted Woodpeckers (Dendrocopos major).

Two new species of Gram-positive cocci were isolated from the uropygial glands of wild woodpeckers (Dendrocopos major) originating from different locations in Germany. A polyphasic approach confirmed the affiliation of the isolates to the genus Kocuria. Phylogenetic analysis based on the 16S rRNA gene showed high degree of similarity to Kocuria koreensis DSM 23367T (99.0% for both isolates). However, low ANIb values of <80% unequivocally separated the new species from K. koreensis. This finding was further corroborated by DNA fingerprinting and analysis of polar lipid profiles. Furthermore, growth characteristics, biochemical tests, MALDI-TOF MS analysis, and G+C contents clearly differentiated the isolates from their known relatives. Besides, the woodpecker isolates significantly differed from each other in their whole-cell protein profiles, DNA fingerprints, and ANIb values. In conclusion, the isolated microorganisms constitute members of two new species, for which the names Kocuria uropygioeca sp. nov. and Kocuria uropygialis sp. nov. are proposed. The type strains are 36T (DSM 101740T=LMG 29265T) and 257T (=DSM 101741T=LMG 29266T) for K. uropygialis sp. nov. and K. uropygioeca sp. nov., respectively.

Nesterenkonia pannonica sp. nov., a novel alkaliphilic and moderately halophilic actinobacterium.

An alkaliphilic and moderately halophilic bacterial strain characterized by optimal growth at pH 9.0-10.0 and with 5-7 % (w/v) NaCl, designated BV-35T, was isolated from water of a soda pan located in Kiskunság National Park, Hungary. Cells of the orange-pigmented colony were Gram-stain-positive, non-motile and non-endospore-forming coccoid rods. The isolate was strictly aerobic, catalase-positive and oxidase-negative. Strain BV-35T displayed a peptidoglycan similar to type A4α, l-Lys-l-Glu (A11.54 according to www.peptidoglycan-types.info) but containing additionally 4-aminobutyric acid. Menaquinone-7 (MK-7) was the predominant isoprenoid quinone, and anteiso-C15 : 0 and anteiso-C17 : 0 were its major cellular fatty acids. The DNA G+C content of strain BV-35T was 65.4 mol%. Based on 16S rRNA gene sequence similarities, the novel isolate showed the closest relationship to Nesterenkonia populi GP 10-3T (97.9 %). The DNA-DNA relatedness between BV-35T and N. populi was 46.7 %. The distinguishing phenotypic and genetic results of this polyphasic study revealed that strain BV-35T represents a novel member of the genus Nesterenkonia, for which the name Nesterenkonia pannonica sp. nov. is proposed. The type strain is BV-35T (=DSM 29786T=NCAIM B 02606T).

First report of Kocuria marina bloodstream infection unrelated to a central venous catheter: a mini-review on an emerging and under-recognized opportunistic pathogen.

We report a case of sepsis by Kocuria marina in a 45-year-old woman carrying a midline venous catheter to provide total parenteral nutrition. Despite the finding of K. marina bacteraemia, no bacteria grew from the culture of the catheter tip. As the patient was affected with severe leg ulcers, K. marina bloodstream infection from a skin breakage other than CVC was supposed. K. marina is an emerging opportunistic agent deserving attention and probably under-recognized, as it can be misdiagnosed as Staphylococcus if only conventional microbiological analyses are performed for bacterial identification.

Peripherally inserted central catheter-related bloodstream infection caused by Kocuria marina in an elderly man.

BACKGROUND: Kocuria species are Gram-positive, aerobic cocci, and members of the Micrcoccaceae family that are known to be opportunistic pathogens. Although there have been sporadic reports of infections caused by Kocuria species, little is known regarding their human pathogenicity and clinical characteristics. CASE REPORT: We herein report a case of a peripherally inserted central catheter (PICC)-related bloodstream infection caused by Kocuria marina in a 90-year-old Japanese with multiple cancer. The patient, who was admitted due to adhesive intestinal obstruction, suddenly developed sepsis on day 29 following admission. Three sets of blood cultures and a culture of the PICC tip revealed the growth of Gram-positive cocci arranged in clusters. The patient improved quickly after treatment with an antimicrobial agent and catheter removal. The organism was identified as Kocuria varians using the MicroScan Walkaway system and K. varians/Kocuria rosea with a 99.7% probability using an API Staph system. However, 16S rRNA gene sequencing analysis identified the pathogen as K. marina. CONCLUSION: Although K. marina is a rare pathogen, physicians should consider it in case of catheter-related infections in patients with serious underlying conditions. As commercial identification systems can misidentify species within the Kocuria genus, the use of genomic methods such as 16S rRNA sequencing and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry may be useful for the precise identification of Kocuria to the species level.

[Unusually infected sebaceous cyst by Dermabacter hominis]. / Un caso inusual de quiste sebáceo infectado por Dermabacter hominis.

Dermabacter hominis species is constituted by Gram positive facultative anaerobic coryneform rods being part of the resident microbiota human skin, and exceptionally associated to infections in immunocompromised or severely debilitated patients. An immunocompetent young adult woman with a neck sebaceous cyst infected by D. hominis as unique etiologic agent is presented. Phenotypic identification of the causative agent was achieved through simple tests, based on the originally scheme proposed by Funke and Bernard, and feasible to be performed in a hospital Microbiology Laboratory. Phenotypic characteristics as coccoid morphology, the acrid/spermatic odor, esculin hydrolysis, the production of pyrrolidonyl-arylamidase, lysine and ornithine decarboxylase, are key tests to identify D. hominis. The matrix-asisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) confirmed the phenotypic identification.

Citricoccus lacusdiani sp. nov., an actinobacterium promoting Microcystis growth with limited soluble phosphorus.

A novel actinobacterium, designated strain JXJ CY 21T, was isolated from the culture mass of Microcystis sp. FACHB-905 collected from Lake Dianchi, South-west China. Polyphasic taxonomic study revealed that the isolate should be a member of the genus Citricoccus. Comparison of the 16S rRNA gene sequence of strain JXJ CY 21T with the available sequences in the GenBank database showed that the strain is closely related to Citricoccus zhacaiensis FS24T (97.8 % similarity), Citricoccus parietis 02-Je-010T (97.7 %), Citricoccus terreus V3M1T (97.6 %), Citricoccus nitrophenolicus PNP1T (97.2 %), Citricoccus alkalitolerans YIM 70010T (97.2 %) and Citricoccus muralis 4-0T (97.0 %). The DNA-DNA hybridization values between strain JXJ CY 21T and the related type strains C. zhacaiensis FS24T and C. parietis 02-Je-010T were 16.0 ± 2.6 and 5.4 ± 1.7 %, respectively. The peptidoglycan in the cell wall was A4α type containing lysine-glutamic acid-glycine. The major respiratory menaquinone was found to be MK-8 (H2) (98.5 %), while the major cellular fatty acids (>10 %) were anteiso-C15:0, iso-C16:0, iso-C15:0 and iso-C14:0. The polar lipids detected were diphosphatidylglycerol, phosphatidylinositol, phosphatidylglycerol, an unidentified phospholipid and an unidentified glycolipid. The DNA G + C content was determined to be 62.7 mol%. Strain JXJ CY 21T can solubilize both insoluble inorganic and organic phosphates up to 24.7 and 1.7 mg/l respectively. This property of the novel actinobacterium acts as a modulator for enhancement of growth of Microcystis sp. FACHB-905 in the lake ecosystem where the amount of soluble phosphate is limited. On the basis of the above taxonomic data, strain JXJ CY 21T represents a novel species of the genus Citricoccus, for which the name Citricoccus lacusdiani sp. nov. is proposed. The type strain is JXJ CY 21T (=KCTC 29653T = DSM 29160T).

Kocuria pelophila sp. nov., an actinobacterium isolated from the rhizosphere of a mangrove.

A novel spherical actinobacterium, designated RS-2-3T, was isolated from the rhizosphere of a mangrove growing on Rambut Island, Indonesia, and its taxonomic position was investigated using a polyphasic approach. Phylogenetic analysis based on 16S rRNA gene sequence comparison revealed that strain RS-2-3T was related to the members of the genus Kocuria. The highest 16S rRNA gene sequence similarity value was observed with Kocuria marina KMM 3905T (97.0 %). The peptidoglycan type of strain RS-2-3T was found to be A3α with an interpeptide bridge comprising l-Ala4-5. The predominant menaquinone was MK-7(H2) and the major fatty acids were anteiso-C15 : 0 and iso-C15 : 0. The DNA G+C content was 71.8 mol%. These characteristics were consistent with those of members of the genus Kocuria. Meanwhile, physiological and biochemical characteristics revealed that strain RS-2-3T differed from the species of the genus Kocuria with validly published names. Therefore, strain RS-2-3T represents a novel species of the genus Kocuria, for which the name Kocuria pelophila sp. nov. is proposed. The type strain is RS-2-3T (=NBRC 110990T=InaCC A704T).

Case of late-onset bleb associated endophthalmitis caused by Rothia mucilaginosa.

Rothia mucilaginosa is a gram-positive coagulase-negative coccus of the family Micrococcaceae. Although R. mucilaginosa forms part of the oropharyngeal microflora, it has only recently been isolated in ocular infections. We report a case of a 41-year-old man who developed late-onset bleb-related endophthalmitis (BRE). He had undergone glaucoma surgery 21 years earlier and had a thin-walled cystic bleb prior to the development of endophthalmitis in his right eye. He immediately received intravitreal injections of ceftazidime and vancomycin, topical levofloxacin and cefmenoxime, and intravenous cefozopran. Culture of the aqueous humor specimen identified R. mucilaginosa by 16S rRNA sequence analysis. To our knowledge, this is the first report of late-onset BRE caused by R. mucilaginosa. Our case indicates that R. mucilaginosa can be a cause of late-onset BRE, and that molecular analysis is an accurate method to identify R. mucilaginosa.