Streptococcus vulneris sp. nov., isolated from wound of patient with diabetic foot ulcer (DFU).

A new α-haemolytic streptococcal strain, designated DM3B3T, was isolated from the wound of a diabetic foot ulcer (DFU) patient. Phylogenetic analysis based on 16S rRNA full-gene sequencing (1563 bp) revealed highest sequence similarity to Streptococcus mitis (99.7%), followed by "Streptococcus gwangjuense" (99.6%), and Streptococcus pseudopneumoniae (99.5%). Comparison of five housekeeping genes, groEL, rpoB, sodA, recA and pheS, revealed that strain DM3B3T was well separated from the Streptococcus reference strains. The complete genome of strain DM3B3T consisted of 1,963,039 bp with a G + C content of 41.0 mol%. Average nucleotide identity values between strain DM3B3T and Streptococcus mitis NCTC 12261T, "Streptococcus gwangjuense" ChDC B345T, and Streptococcus pseudopneumoniae ATCC BAA-960T were 93.8%, 94.4%, and 92.2%, respectively. The highest digital DNA-DNA hybridization value with respect to the closest species was 57.5%, i.e., below the species cut-off of 70% hybridization. The main cellular fatty acids of strain DM3B3T were 16:0, 18:1ω7c, 18:1ω9c and 18:0. On the basis of phylogenetic, genotypic and phenotypic data, we propose to classify this isolate as representative of a novel species of the genus Streptococcus, Streptococcus vulneris sp. nov., in reference to its isolation from wound, with strain DM3B3T (= NBRC 114638T = BCRC 81288T) as the type strain.

Punicalagin induces apoptotic and autophagic cell death in human U87MG glioma cells.

AIM: To investigate the effects of punicalagin, a polyphenol isolated from Punica granatum, on human U87MG glioma cells in vitro. METHODS: The viability of human U87MG glioma cells was evaluated using MTT assay. Cell cycle was detected with flow cytometry analysis. The levels of Bcl-2, cleaved caspase-9, cleaved poly(ADP-ribose) polymerase (PARP), phosphor-AMPK and phosphor-p27 at Thr198 were measured using immunoblot analyses. Caspase-3 activity was determined with spectrophotometer. To determine autophagy, LC3 cleavage and punctate patterns were examined. RESULTS: Punicalagin (1-30 µg/mL) dose-dependently inhibited the cell viability in association with increased cyclin E level and decreased cyclin B and cyclin A levels. The treatment also induced apoptosis as shown by the cleavage of PARP, activation of caspase-9, and increase of caspase-3 activity in the cells. However, pretreatment of the cells with the pan-caspase inhibitor z-DEVD-fmk (50 µmol/L) did not completely prevent the cell death. On the other hand, punicalagin treatment increased LC3-II cleavage and caused GFP-LC3-II-stained punctate pattern in the cells. Suppressing autophagy of cells with chloroquine (1-10 µmol/L) dose-dependently alleviated the cell death caused by punicalagin. Punicalagin (1-30 µg/mL) also increased the levels phosphor-AMPK and phosphor-p27 at Thr198 in the cells, which were correlated with the induction of autophagic cell death. CONCLUSION: Punicalagin induces human U87MG glioma cell death through both apoptotic and autophagic pathways.