Whole-genome sequencing of Aminobacterium sp. strain MB27-C1, isolated from the wastewater treatment plant of a steel mill.

Here, we report the complete genome sequence of Aminobacterium sp. strain MB27-C1, which was isolated from sewage sludge collected at the wastewater treatment plant of Sanming Steel Co. Ltd. in Fujian, China. The resulting genome of strain MB27-C1 is a single contig of 2,427,830 bp with 41.58% GC content.

Complete genome sequence of Anaerotignum sp. strain MB30-C6, isolated from sewage sludge of the wastewater treatment plant at a steel factory.

We report the complete genome sequence of Anaerotignum sp. strain MB30-C6, which was isolated from the dehydrated sludge collected at the wastewater treatment plant of Sanming Steel Co. Ltd. in Fujian, China. The resulting genome of strain MB30-C6 is a single contig of 3,104,838 bp with 39.49% GC content.

Circulating androgen regulation by androgen-catabolizing gut bacteria in male mouse gut.

Abnormally high circulating androgen levels have been considered a causative factor for benign prostatic hypertrophy and prostate cancer in men. Recent animal studies on gut microbiome suggested that gut bacteria are involved in sex steroid metabolism; however, the underlying mechanisms and bacterial taxa remain elusive. Denitrifying betaproteobacteria Thauera spp. are metabolically versatile and often distributed in the animal gut. Thauera sp. strain GDN1 is an unusual betaproteobacterium capable of catabolizing androgen under both aerobic and anaerobic conditions. We administered C57BL/6 mice (aged 7 weeks) with strain GDN1 through oral gavage. The strain GDN1 administration caused a minor increase in the relative abundance of Thauera (≤0.1%); however, it has profound effects on the host physiology and gut bacterial community. The results of our ELISA assay and metabolite profile analysis indicated an approximately 50% reduction in serum androgen levels in the strain GDN1-administered male mice. Moreover, androgenic ring-cleaved metabolites were detected in the fecal extracts of the strain GDN1-administered mice. Furthermore, our RT - qPCR results revealed the expression of the androgen catabolism genes in the gut of the strain GDN1-administered mice. We found that the administered strain GDN1 regulated mouse serum androgen levels, possibly because it blocked androgen recycling through enterohepatic circulation. This study discovered that sex steroids serve as a carbon source of gut bacteria; moreover, host circulating androgen levels may be regulated by androgen-catabolizing gut bacteria. Our data thus indicate the possible applicability of androgen-catabolic gut bacteria as potent probiotics in alternative therapy of hyperandrogenism.

Phocaeicola oris sp. nov., an anaerobic bacterium isolated from the saliva of a patient with oral squamous cell carcinoma.

A Gram-stain-negative or -positive, strictly anaerobic, non-spore-forming and pleomorphic bacterium (designated 14-104T) was isolated from the saliva sample of a patient with oral squamous cell carcinoma. It was an acid-tolerant neutralophilic mesophile, growing at between 20 and 40 °C (with optimum growth at 30 °C) and pH between pH 3.0 and 7.0 (with optimum growth at pH 6.0-7.0). It contained anteiso-C15 : 0 and C15 : 0 as the major fatty acids. The genome size of strain 14-104T was 2.98 Mbp, and the G+C content was 39.6 mol%. It shared <87 % 16S rRNA sequence similarity, <71 % orthologous average nucleotide identity, <76 % average amino acid identity and <68 %% of conserved proteins with its closest relative, Phocaeicola abscessus CCUG 55929T. Reconstruction of phylogenetic and phylogenomic trees revealed that strain 14-104T and P. abscessus CCUG 55929T were clustered as a distinct clade without any other terminal node. The phylogenetic and phylogenomic analyses along with physiological and chemotaxonomic data indicated that strain 14-104T represents a novel species in the genus Phocaeicola, for which the name Phocaeicola oris sp. nov. is proposed. The type strain is 14-104T (=BCRC 81305T= NBRC 115041T).

Estrogen Degraders and Estrogen Degradation Pathway Identified in an Activated Sludge.

The environmental release and fate of estrogens are becoming an increasing public concern. Bacterial degradation has been considered the main process for eliminating estrogens from wastewater treatment plants. Various bacterial isolates are reportedly capable of aerobic estrogen degradation, and several estrogen degradation pathways have been proposed in proteobacteria and actinobacteria. However, the ecophysiological relevance of estrogen-degrading bacteria in the environment is unclear. In this study, we investigated the estrogen degradation pathway and corresponding degraders in activated sludge collected from the Dihua Sewage Treatment Plant, Taipei, Taiwan. Cultivation-dependent and cultivation-independent methods were used to assess estrogen biodegradation in the collected activated sludge. Estrogen metabolite profile analysis revealed the production of pyridinestrone acid and two A/B-ring cleavage products in activated sludge incubated with estrone (1 mM), which are characteristic of the 4,5-seco pathway. PCR-based functional assays detected sequences closely related to alphaproteobacterial oecC, a key gene of the 4,5-seco pathway. Metagenomic analysis suggested that Novosphingobium spp. are major estrogen degraders in estrone-amended activated sludge. Novosphingobium sp. strain SLCC, an estrone-degrading alphaproteobacterium, was isolated from the examined activated sludge. The general physiology and metabolism of this strain were characterized. Pyridinestrone acid and the A/B-ring cleavage products were detected in estrone-grown strain SLCC cultures. The production of pyridinestrone acid was also observed during the aerobic incubation of strain SLCC with 3.7 nM (1 µg/liter) estrone. This concentration is close to that detected in many natural and engineered aquatic ecosystems. The presented data suggest the ecophysiological relevance of Novosphingobium spp. in activated sludge.IMPORTANCE Estrogens, which persistently contaminate surface water worldwide, have been classified as endocrine disruptors and human carcinogens. We contribute new knowledge on the major estrogen biodegradation pathway and estrogen degraders in wastewater treatment plants. This study considerably advances the understanding of environmental estrogen biodegradation, which is instrumental for the efficient elimination of these hazardous pollutants. Moreover, this study substantially improves the understanding of microbial estrogen degradation in the environment.

Biochemical Mechanisms and Catabolic Enzymes Involved in Bacterial Estrogen Degradation Pathways.

Estrogens have been classified as group 1 carcinogens by the World Health Organization and represent a significant concern given that they are found in surface waters worldwide, and long-term exposure to estrogen-contaminated water can disrupt sexual development in animals. To date, the estrogen catabolic enzymes and genes remain unknown. Using a tiered functional genomics approach, we identified three estrogen catabolic gene clusters in Sphingomonas sp. strain KC8. We identified several estrone-derived compounds, including 4-hydroxyestrone, a meta-cleavage product, and pyridinestrone acid. The yeast-based estrogen assay suggested that pyridinestrone acid exhibits negligible estrogenic activity. We characterized 17ß-estradiol dehydrogenase and 4-hydroxyestrone 4,5-dioxygenase, responsible for the 17-dehydrogenation and meta-cleavage of the estrogen A ring, respectively. The characteristic pyridinestrone acid was detected in estrone-spiked samples collected from two wastewater treatment plants and two suburban rivers in Taiwan. The results significantly expand our understanding of microbial degradation of aromatic steroids at molecular level.

Combined vitamin C sonophoresis and neodymium-doped yttrium aluminum garnet (NdYAG) laser for facial hyperpigmentation: An outcome observation study in Asian patients.

BACKGROUND: The neodymium-doped yttrium aluminum garnet (NdYAG) laser therapy has been a popular technique for facial rejuvenation but certain adverse effects like post-inflammatory hyperpigmentation are issues of concern to Asian patients. AIMS: To assess the outcome following combined treatment with vitamin C sonophoresis and NdYAG laser, in selected cases of facial hyperpigmentation. METHODS: Twenty three women with dyschromia or melasma who had undergone five sessions of Q-switched NdYAG laser therapy followed by transdermal delivery of vitamin C via sonophoresis were selected after a retrospective review of case records. The objective and subjective clinical outcomes and the side effects, including erythema, scaling, pruritus, dryness and post-inflammatory hyperpigmentation were evaluated. RESULTS: In both objective or subjective outcomes, 91.3% (21/23) of the patients showed an excellent or better outcome, while 8.7% (2/23) showed no change. A majority of the patients (73.9%, 17/23) experienced no post-inflammatory hyperpigmentation or had slight post-inflammatory hyperpigmentation which quickly resolved within 1 week. Only one (4.3%) patient had extreme post-inflammatory hyperpigmentation which lasted for over a month. LIMITATIONS: This was a retrospective study without a control group; a comparative study with a control group (patients treated with the laser alone, without vitamin C sonopheresis) is needed to determine the difference in the outcome. CONCLUSION: The use of vitamin C sonophoresis along with NdYAG laser may reduce the incidence of adverse effects in Asian patients. Patients experienced obvious improvement in hyperpigmentation and had lower chances of experiencing extreme or severe post-inflammatory hyperpigmentation.

Analysis of the AAA+ chaperone clpB gene and stress-response expression in the halophilic methanogenic archaeon Methanohalophilus portucalensis.

ClpB is a member of the protein-disaggregating chaperone machinery belonging to the AAA+ superfamily. This paper describes a new clpB gene from the halophilic methanoarchaeon Methanohalophilus portucalensis, which has not been reported previously in Archaea. The partial sequence of clpB was identified from the investigation of the salt-stress response of Meh. portucalensis by differential-display RT-PCR (DDRT-PCR). Furthermore, the complete clpB sequence (2610 nt) and its upstream genes encoding the type I chaperonin GroEL/ES were obtained through inverse PCR, Southern hybridization and sequencing. The G+C ratio of clpB is 49.6 mol%. The predicted ClpB polypeptide contains 869 aa and possesses a long central domain and a predicted distinctly discontinuous coiled-coil motif separating two nucleotide-binding domains (NBD1 and NBD2). NBD1 has a single Walker A and two Walker B motifs and NBD2 has only one of each Walker motif, a characteristic of HSP100 proteins. Two repeated Clp amino-terminal domain motifs (ClpN) were identified in ClpB. The putative amino acid sequence shared 75.6 % identity with the predicted clpB homologue annotated as ATPase AAA-2 of Methanococcoides burtonii DSM 6242. Preliminary phylogenetic analysis clustered Meh. portucalensis ClpB (MpClpB) with the low G+C Gram-positive bacteria. Stress response analysis of clpB by Northern blotting showed up to 1.5-fold increased transcription levels in response to both salt up-shock (from 2.1 to 3.1 M NaCl) and down-shock (from 2.1 to 0.9 M NaCl). Both clpB and groEL/ES transcript levels increased when the temperature was shifted from 37 degrees C to 55 degrees C. Under heat stress clpB transcription was repressed by the addition of the osmolyte betaine (1 mM). In conclusion, a novel AAA+ chaperone clpB gene from a halophilic methanogen that responded to the fluctuations in temperature, salt concentration and betaine has been identified and analysed for the first time.