Clostridium butyricum is a butyric acid-producing anaerobic bacteriuma, and commonly present as gut microbiota in humans. This species has been used as a probiotic for the prevention of diarrhea in humans. In this study, we report the draft genome of C. butyricum DKU-01, which was isolated from infant feces, to better understand the characteristics of this strain so that it can later be used in the development of probiotic products. A total of 79 contigs generated by hybrid assembly of sequences obtained from Roche 454 and Illumina Miseq sequencing systems were investigated. The assembled genome of strain DKU-01 consisted of 4,519,722 bp (28.62% G + C content) with a N50 contig length of 108,221 bp and 4,037 predicted CDSs. The extracted 16S rRNA gene from genome sequences of DKU-01 was similar to Clostridium butyricum with 99.63% pairwise similarity. The sequence of strain DKU-01 was compared with previously reported genome sequences of C. butyricum. The value of average nucleotide identity between strains DKU-01 and C. butyricum 60E3 was 98.74%, making it the most similar strain to DKU-01. We sequenced the DKU-01 strain isolated from infant feces, and compared it with the available genomes of C. butyricum on a public database. Genes related to Fructooligosaccharide utilization were detected in the genome of strain DKU-01 and compared with other genera, such as Bifidobacterium and Streptococcus. We found that strain DKU-01 can metabolize a wide range of carbohydrates in comparative genome result. Further analyses of the comparative genome and fermentation study can provide the information necessary for the development of strain DKU-01 for probiotics.
9 April 2021 in International Journal of Systematic and Evolutionary Microbiology
Soybean pods, separated and enclosed from the outside environment, are considered a suitable place to find new microbes. A Gram-stain-negative, aerobic bacterium, bacterial strain (YB22T) was isolated from the pod of Glycine max (soybean) collected from a rural area in Republic of Korea and characterized by using polyphasic taxonomy. Cells of the strain were rod-shaped (approximately 0.4–0.6 µm wide and 4.0–5.0 µm long), non-flagellated and formed silver-yellow colonies. Cells grew at 25–35 °C (optimum, 28–30 °C), at pH 5.0–9.0 (optimum, pH 7.0) and with 0–2.0% NaCl (optimum, 0 % NaCl). 16S rRNA gene sequencing showed that strain YB22T was phylogenetically closest to the genus Elizabethkingia, and showed highest similarities to Elizabethkingia occulta G4070T (96.7 %), Elizabethkingia meningoseptica ATCC 13253T (96.7 %), Elizabethkingia miricola DSM 14571T (96.6 %), Elizabethkingia bruuniana G0146T (96.5 %), Elizabethkingia ursingii G4122T (96.4 %) and Elizabethkingia anophelis R26T (96.2 %). Average amino acid identity values between strain YB22T and other taxa in the genus Elizabethkingia were all above the threshold range of genus determination. Average nucleotide identity and digital DNA–DNA hybridization values between strain YB22T and other phylogenetic relatives were all found to be below the threshold range for species determination. The respiratory quinone of strain YB22T was menaquinone 6 (MK-6) and the predominant cellular fatty acids were iso-C15 : 0 (47.8 %) and iso-C17 : 0 3-OH (18.5 %). The major polar lipids were phosphatidylethanolamine, four unidentified aminolipids and three unidentified polar lipids. The phylogenetic analysis and physiological and biochemical data showed that strain YB22T should represent a novel species in the genus Elizabethkingia, for which the name Elizabethkingia argenteiflava sp. nov. is proposed. The type strain for this novel species is YB22T (=KCCM 43263T=JCM 32097T).
A FK506 analogue containing a non-natural starter unit was obtained through mutasynthesis by feeding cultures of Streptomyces sp. KCTC 11604BP fkbO deletion mutant with 3-cyclohexene-1-carboxylic acid. The structure of the new compound, 32-dehydroxy-FK506, and its biological activities were determined.
1 June 2023 in Clinical, Cosmetic and Investigational Dermatology
Background: Various laser- and light-based devices have been introduced as complementary or alternative treatment modalities for dermatophytosis, particularly for finger or toenail onychomycosis. Objective: This study aimed to comparatively evaluate the antifungal effects of 405-nm and 635-nm dual-band diode lasers using an in vivo guinea pig model of dermatophytosis. Materials and Methods: A guinea pig model was developed by the repetitive application of fungal spore preparations to the back skin of guinea pigs. Dual-diode laser treatment was delivered to the guinea pig skin at a power of 24 mW at a wavelength of 405 nm and 18 mW at 635 nm for 12 min. The treatments were administered three times weekly for 2 weeks, and a mycological study was performed. Results: Mycological studies using scraped samples obtained from treatment groups A (N = 8) and B (N = 8) after dual-diode laser treatment revealed that seven of eight (87.5%) samples in each group had negative results for direct potassium hydroxide microscopy and fungal culture studies. Skin specimens from each infected laser-untreated guinea pig exhibited spongiotic psoriasiform epidermis with parakeratosis. Meanwhile, skin specimens from infected laser-treated guinea pigs in groups A and B demonstrated thinner epidermal thickness than those from infected untreated controls but thicker than those from uninfected treated controls without noticeable inflammatory cell infiltration in the dermis. Conclusion: The guinea pig dermatophytosis model can be used to comparatively evaluate the efficacy and safety of various treatment modalities, including dual-diode lasers, for superficial fungal skin infection.
31 December 2016 in Journal of Applied Biological Chemistry