Chloroperoxidase production by Caldariomyces fumago biofilms

Chloroperoxidase (CPO) is a versatile enzyme, which is secreted by the marine fungus Caldariomyces fumago (Leptoxyphium fumago). However, the application of the enzyme is hampered by its high price, which is due to the costly, labor‐intensive purification process. One challenge of the downstream process is the removal of a coproduced black pigment that forms a complex with the active enzyme. While strain development can be considered as an option to reduce the synthesis of the interfering pigment, the metabolism of the microorganism can be altered alternatively by using the biofilm growth mode of the fungus. The aim of this study was to reduce pigment formation during CPO synthesis. We investigated for the first time CPO production during C. fumago biofilm growth initiated through the presence of different microstructured stainless steel surfaces (material number: 1.4571; AISI 316Ti). CPO production by C. fumago was similar when grown as a biofilm or in suspension, whereas pigment formation was drastically reduced by cells grown on moderately structured surfaces (R_a = 0.13 ± 0.02 μm). The possibilities of biofilm growth for changing cell properties and for continuous fermentation are discussed.     

Long-Term Prognostic Analysis after Endoscopic Endonasal Surgery for Olfactory Neuroblastoma: A Retrospective Study of 13 Cases

ObjectivesTo summarize the characteristics and long–term outcomes of olfactory neuroblastoma through the analysis of 13 cases in single institution, with the assessment of treatment modality, prognostic factors.MethodA retrospective study of thirteen cases diagnosed as olfactory neuroblastoma and underwent combined treatments during the period 2000–2010. Statistical analysis was performed to search for prognostic factors and compared different treatment modalities.Results13 patients were enrolled in this study, including 8 male and 5 female, ranging from 15 to 69 (median 43) years old. One patient at stage A was only treated with endoscopic endonasal surgery (EES). Seven patients were treated with preoperative radiotherapy and EES, two with EES and postoperative radiotherapy, and the other three with combined radiotherapy and chemotherapy. The range of follow-up time varied from 23 to 116 months (median 65 months). The 5-year overall survival rate was 46.2% (6/13). To date, these thirteen patients have not suffered local recurrences while two patients had lymph node recurrences and one had distant metastasis in the bone marrow. In 13 patients, 61.5% were diagnosed as late T stage (T3/4), 69.2% late Kadish stage (C/D) and 53.8% were high Hyams grade (I/ II), which indicated poor prognosis. Related prognostic factors were the TNM stage (T stage P = 0.028, N stage P = 0.000, M stage P = 0.007), Kadish stage (P = 0.025) and treatment modality (P = 0.015).ConclusionLate stage of TNM and Kadish staging system indicated a poor prognosis. Combined treatment modality, including endoscopic endonasal surgery, achieved a better outcome than non-surgical approach.     

Polysomnographic Characteristics of Sleep in Stroke: A Systematic Review and Meta-Analysis

BackgroundResearch on sleep after stroke has focused mainly on sleep disordered breathing. However, the extend to which sleep physiology is altered in stroke survivors, how these alterations compare to healthy volunteers, and how sleep changes might affect recovery as well as physical and mental health has yet to be fully researched. Motivated by the view that a deeper understanding of sleep in stroke is needed to account for its role in health and well-being as well as its relevance for recovery and rehabilitation, we conducted a systematic review and meta-analysis of polysomnographic studies comparing stroke to control populations.MethodMedline and PsycInfo databases were searched using "stroke" and words capturing polysomnographic parameters as search terms. This yielded 1692 abstracts for screening, with 15 meeting the criteria for systematic review and 9 for meta-analysis. Prisma best practice guidelines were followed for the systematic review; the Comprehensive Meta-Analysis software was used for random effects modelling.ResultsThe meta-analysis revealed that patients with stroke have poorer sleep than controls. Patients had lower sleep efficiency (mean 75% vs 84%), shorter total-sleep-time (309.4 vs 340.3 min) and more wake-after-sleep-onset (97.2 vs 53.8 min). Patients also spend more time in stage 1 (13% vs 10%) and less time in stage 2 sleep (36% vs 45%) and slow-wave-sleep (10% vs 12%). No group differences were identified for REM sleep. The systematic review revealed a strong bias towards studies in the early recovery phase of stroke, with no study reporting specifically on patients in the chronic state. Moreover, participants in the control groups included community samples as well as other patients groups.ConclusionsThese results indicate poorer sleep in patients with stroke than controls. While strongly suggestive in nature, the evidence base is limited and methodologically diverse, and hands a clear mandate for further research. A particular need regards polysomnographic studies in chronic community-dwelling patients compared to age-matched individuals.     

On the Evolutionary History of Uleiella chilensis,a Smut Fungus Parasite of Araucaria araucana in South America: Uleiellales ord. nov. in Ustilaginomycetes

The evolutionary history, divergence times and phylogenetic relationships of Uleiella chilensis (Ustilaginomycotina, smut fungi) associated with Araucaria araucana were analysed. DNA sequences from multiple gene regions and morphology were analysed and compared to other members of the Basidiomycota to determine the phylogenetic placement of smut fungi on gymnosperms. Divergence time estimates indicate that the majority of smut fungal orders diversified during the Triassic–Jurassic period. However, the origin and relationships of several orders remain uncertain. The most recent common ancestor between Uleiella chilensis and Violaceomyces palustris has been dated to the Lower Cretaceous. Comparisons of divergence time estimates between smut fungi and host plants lead to the hypothesis that the early Ustilaginomycotina had a saprobic lifestyle. As there are only two extant species of Araucaria in South America, each hosting a unique Uleiella species, we suggest that either coevolution or a host shift followed by allopatric speciation are the most likely explanations for the current geographic restriction of Uleiella and its low diversity. Phylogenetic and age estimation analyses, ecology, the unusual life-cycle and the peculiar combination of septal and haustorial characteristics support Uleiella chilensis as a distinct lineage among the Ustilaginomycotina. Here, we describe a new ustilaginomycetous order, the Uleiellales to accommodate Uleiella. Within the Ustilaginomycetes, Uleiellales are sister taxon to the Violaceomycetales.     

Cloning and characterization of three ketoreductases from soil metagenome for preparing optically active alcohols

Objectives

To discover novel ketoreductases (KRED) from soil metagenome preparation of chiral alcohols.

Results

Three putative KRED were cloned, heterologously expressed in Eschericha coli and characterized based on the sequence analysis of soil metagenome. All the three enzymes (KRED424, KRED432, and KRED433) had maximum activity at 55 °C and pH 7. KRED424 had a broader substrate spectrum compared with the other two. Three prochiral carbonyl compounds were used to evaluate the abilities of enantioselective reductions of the KRED. For N-Boc-3-pyrrolidone, all enzymes produced an (S)-type alcohol in enantiomeric excess (>99 % ee). For ethyl 2-oxo-4-phenylbutyrate, KRED424 showed a higher conversion (91.5 %) and enantioselectivity (S-type, >99 % ee) than KRED432 and KRED433. For ethyl 4-chloroacetoacetate (COBE), both of KRED424 and KRED433 completely converted 20 mM substrate and KRED433 could obtain an (R)-alcohol with 94 % ee.

Conclusions

The three ketoreductases have potential in the preparation of pharmaceuticals and fine chemicals.