Taklimakanibacter deserti gen. nov., sp. nov. and Taklimakanibacter lacteus sp. nov., isolated from desert soil.

Two Gram-stain-negative, aerobic, milk-white coloured, non-motile, short rod-shaped bacteria, designated as strains SYSU D60010T and SYSU D60012T, were isolated from sand samples collected from the Taklimakan Desert of Xinjiang Province in China. Both strains were positive for oxidase, catalase and nitrate reduction, but negative for amylase, H2S production, hydrolysis of gelatin and cellulase. Strains SYSU D60010T and SYSU D60012T grew well at 28 °C, at pH 7 and had the same NaCl tolerance range of 0-1 % (w/v). The major fatty acids (>5 %) of strains SYSU D60010T and SYSU D60012T were summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c), iso-C19 : 0 cyclo ω8c, C16 : 0 and iso-C18 : 1 2-OH. Q-10 was the only respiratory ubiquinone. Strains SYSU D60010T and SYSU D60012T showed high 16S rRNA gene sequence similarities to Aestuariivirga litoralis SYSU M10001T (94.2 and 94.1 %), Rhodoligotrophos jinshengii BUT-3T (92.0 and 91.9 %) and Rhodoligotrophos appendicifer 120-1T (91.8 and 91.7 %), and the genomes were 7.4 and 5.8 Mbp in size with DNA G+C contents of 62.8 and 63.0 mol%, respectively. Phylogenetic, phenotypic and chemotaxonomic characteristics indicated that these two strains represent a novel genus and two novel species within the family Aestuariivirgaceae. We propose the name Taklimakanibacter deserti gen. nov., sp. nov. for strain SYSU D60010T, representing the type strain of this species (=KCTC 52783T =NBRC 113344T) and Taklimakanibacter lacteus gen. nov., sp. nov. for strain SYSU D60012T, representing the type strain of this species (=KCTC 52785T=NBRC 113128T).

Bacteria-responsive drug release platform for the local treatment of bacterial vaginosis.

Bacterial vaginosis (BV) is a common vaginal infection affecting millions of women. Vaginal anaerobic dysbiosis occurs when Lactobacillus spp., the dominant flora in healthy vagina is replaced by certain overgrown anaerobes, resulting in unpleasant symptoms such as vaginal discharge and odor. With a high recurrence rate, BV also severely impacts the overall quality of life of childbearing women by inducing preterm delivery and increasing the risks of pelvic inflammatory disease and sexually transmitted infections. Among various BV-associated bacteria, Gardnerella vaginalis (G. vaginalis) has been identified as a primary pathogen since it has been isolated from almost all women carrying BV and exhibits higher virulence potential over other bacteria. When dealing with BV relapse, intravaginal drug delivery systems are superior to conventional oral antibiotic therapies in improving therapeutic efficacy owing to more effective drug dose, reduced drug resistance and minimized side effects such as stomach irritation. Traditional intravaginal drug administration generally involves solids, semi-solids and delivery devices inserted into the vaginal lumen to achieve sustained drug release. However, they are mostly designed for continuous drug release and are not preventative therapies, resulting in severe side effects caused by excess dosing. Stimuli-responsive systems that can release drug only when needed ("on-demand") can help diminish these negative side effects. Hence, we developed a bacteria-responsive liposomal platform for the prevention and treatment of BV. This platform demonstrated sustained drug release in the presence of vaginolysin (VLY), a toxin secreted specifically by G. vaginalis. We prepared four liposome formulations and evaluated their responsiveness to G. vaginalis. The results demonstrated that the liposome formulations could achieve cumulative drug release ranging from 46.7% to 51.8% over a 3-5 day period in response to G. vaginalis and hardly any drug release in the presence of Lactobacillus crispatus (L. crispatus), indicating the high specificity of the system. Overall, the bacteria-responsive drug release platform has great potential, since it will be the first time to realize sustained drug release stimulated by a specific pathogen for BV prevention and treatment. This on-demand therapy can potentially provide relief to the millions of women affected by BV. .

Desertibaculum subflavum gen. nov., sp. nov., a novel member of the family Sneathiellaceae isolated from the Kumtag Desert soil.

A novel rod-shaped bacterium, designated as strain SYSU D60015T that formed yellowish colonies was isolated from a sandy soil collected from the Kumtag Desert in Xinjiang, China. Cells were Gram-stain-negative, oxidase-positive, catalase-negative and motile with a single polar flagellum. Growth optimum occurred between 28 and 37 °C, pH 7.0 and with 0-0.5% (W/V) NaCl. The predominant cellular fatty acids (> 5%) were summed feature 8 (C18:1 ω7c and/or C18:1 ω6c), C19:0 cyclo ω8c, C18:1 ω7c 11-methyl and C16:0. The polar lipid profile contained one phosphatidylethanolamine, one diphosphatidylglycerol, one phosphatidylglycerol, one unidentified phospholipid, three unidentified aminolipids, two unidentified aminophospholipids and seven unidentified lipids. The only respiratory quinone was ubiquinone-10. Based on 16S rRNA gene sequence phylogenetic analysis, strain SYSU D60015T was found to form a distinct linage within the family Sneathiellaceae, and had 16S rRNA gene sequence similarities of 90.8% to Taonella mepensis H1T, and 90.2% to Ferrovibrio denitrificans S3T. The genome of SYSU D60015T was 5.66 Mb in size with 68.2% of DNA G + C content. The low digital DNA-DNA hybridization (dDDH, 18.0%), average nucleotide identity (ANI, 77.5%) and amino acid identity (AAI, 56.0%) values between SYSU D60015T and Ferrovibrio terrae K5T indicated that SYSU D60015T might represent a distinct genus. Based on the phylogenetic, phenotypic, chemotaxonomic and genomic data, we propose Desertibaculum subflavum gen. nov., sp. nov. as a novel species of a new genus within the family Sneathiellaceae. The type strain is SYSU D60015T (= NBRC 112952T = CGMCC 1.16256T).

Rubellimicrobium arenae sp. nov., isolated from desert soil.

Two Gram-stain-negative strains, designated as SYSU D00286T and SYSU D00782, were isolated from a sand sample collected from the Kumtag Desert in Xinjiang, north-west China. Cells were aerobic, non-motile and positive for both oxidase and catalase. Growth occurred at 4-37 °C (optimum, 28-30 °C), pH 6.0-7.0 (optimum, pH 7.0) and NaCl concentration of 0-1.5 % (w/v; optimum, 0%). Growth was observed on Reasoner's 2A agar and nutrient agar, but not on Luria-Bertani agar and trypticase soy agar. The polar lipids were identified as diphosphatidylglycerol, phosphatidylcholine, phosphatidylglycerol, three unidentified aminolipids, one unidentified glycolipid and two unidentified phospholipids. The major respiratory quinone was ubiquinone-10 and the major fatty acids (>10 %) were C16 : 0 and summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c). The 16S rRNA gene sequence similarity between strains SYSU D00286T and SYSU D00782 was 100%, and their average nucleotide identity (ANI), average amino acid identity and (AAI) digital DNA-DNA hybridization (dDDH) values were all 100.0 %. Phylogenetic analysis indicated that these two strains belong to the same species of the genus Rubellimicrobium and show the highest sequence similarity to Rubellimicrobium rubrum KCTC 72461T (98.2 %) and Rubellimicrobium roseum CCTCC AA 208029T (97.5 %). The ANI, AAI and dDDH values between SYSU D00286T (as well as SYSU D00782) and the other five Rubellimicrobium type strains were all less than or equal to 83.2, 80.1 and 23.6 %, respectively. Based on their phylogenetic, phenotypic and chemotaxonomical features, strains SYSU D00286T and SYSU D00782 represent a novel species of the genus Rubellimicrobium, for which the name Rubellimicrobium arenae sp. nov. is proposed. The type strain is SYSU D00286T (=MCCC 1K04981T=CGMCC 1.8626T=KCTC 82271T).

Telluribacter roseus sp. nov., Isolated from the Kumtag Desert Soil.

A pink-pigmented bacterium, designated as strain SYSU D00476T, was isolated from sandy soil collected from the Kumtag Desert in China. Colonies were opaque, smooth and of a slight convexity with a clearly defined border. Cells were rod-shaped, Gram-stain-negative, catalase- and oxidase-positive. Growth occurred at 4-45 ℃ (optimum at 28-30 ℃), pH 6.0-8.0 (optimum at 7.0), and with 0-3.0% NaCl (w/v, optimum at 0-2.0%). Major fatty acids (> 10%) were C16:0, summed feature 3 (C16:1 ω7c and/or C16:1 ω6c), iso-C17:0 3-OH and iso-C15:0. Polar lipids comprised of three unidentified polar aminolipids (ALs), two unidentified aminophosphoglycolipids (APLs), one unidentified glycolipid (GL) and three unidentified phospholipids (PLs). The predominant respiratory quinone was MK-7. The genomic DNA G + C content was 50.5%. The low digital DNA-DNA hybridization (dDDH, 27.4%) and average nucleotide identity (ANI, 85%) values between strain SYSU D00476T and Telluribacter humicola KCTC 42819T indicated that SYSU D00476T represent a distinct species. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain SYSU D00476T belonged to the genus Telluribacter, showing 97.5% similarity with T. humicola KCTC 42819T. All these data support that strain SYSU D00476T represent a novel species of the genus Telluribacter within the family Spirosomataceae, named as Telluribacter roseus sp. nov. The type strain is SYSU D00476T (= KCTC 82285T = CGMCC 1.18647T = MCCC 1K04983T).

Conjugated Polymer Nanoparticles Based Fluorescent Electronic Nose for the Identification of Volatile Compounds.

A fluorescence sensing array (or fluorescent electronic nose) is designed on a disposable paper card using 36 sets of soluble conjugated polymeric nanoparticles (SCPNs) as sensors to easily identify wide ranges of volatile analytes, including explosives and toxic industrial chemicals (amines and pungent acids). A 108-dimensional vector obtained from the fluorescent color change in the sensing array is defined and directly treated as an index in a standard chemical library (30 kinds of volatile analytes and a control group). Hierarchical clustering analysis (HCA) and principal component analysis (PCA) indicated the diversity in electronic structures; saturated vapor pressure and miscibility of analytes are keys in differentiating the analytes, with electron-rich arenes and alkylamines enhancing fluorescence and electron-deficient analytes attenuating fluorescence. A support vector machine (SVM) works well to predict an unknown sample, reaching 99.5% accuracy. The excellent fluorescence stability (no fluorescence quenching after being exposed in air for one month) and high sensitivity (emission color changes within minutes when exposed to analytes) suggest that the fluorescent polymer-based electronic nose will play an important role in field detection and identification of a wide spreading of hazardous substances.

Doxorubicin nanoformulations on therapy against cancer: An overview from the last 10 years.

Doxorubicin (DOX) is a natural antibiotic with antineoplastic activity. It has been used for over 40 years and remains one of the most used drugs in chemotherapy for a variety of cancers. However, cardiotoxicity limits its use for long periods. To overcome this limitation, encapsulation in smart drug delivery systems (DDS) brings advantages in comparison with free drug administration (i.e., conventional anticancer drug therapy). In this review, we present the most relevant nanostructures used for DOX encapsulation over the last 10 years, such as liposomes, micelles and polymeric vesicles (i.e., polymersomes), micro/nanoemulsions, different types of polymeric nanoparticles and hydrogel nanoparticles, as well as novel approaches for DOX encapsulation. The studies highlighted here show these nanoformulations achieved higher solubility, improved tumor cytotoxicity, prolonged DOX release, as well as reduced side effects, among other interesting advantages.