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Background Enteral virus infections and early introduction of cow's milk (CM)-based formula are among the suggested triggers of type 1 diabetes (T1D)-associated autoimmunity, although studies on their role have remained contradictory. Here, we aimed to analyse whether interactions between these factors might clarify the controversies. Materials The study population comprised 107 subjects developing positivity for at least two T1D-associated autoantibodies and 446 control subjects from the Finnish diabetes prediction and prevention cohort. Enterovirus, rotavirus, adenovirus, respiratory syncytial virus and bovine insulin-binding antibodies were analysed from prospective serum samples at 3–24 months of age. Data on infant cow's milk exposure were available for 472 subjects: 251 subjects were exposed to cow's milk before 3 months of age and 221 subjects later in infancy. Results Signs of an enterovirus infection by 12 months of age were associated with the appearance of autoimmunity among children who were exposed to cow's milk before 3 months of age. Cox regression analysis revealed a combined effect of enterovirus infection and early cow's milk exposure for the development of ICA and any of the biochemically defined autoantibodies (p = 0.001), of IAA (p = 0.002), GADA (p = 0.001) and IA-2A (p = 0.013). Conclusions The effect of enterovirus infection on the appearance of T1D-associated autoimmunity seems to be modified by exposure to cow's milk in early infancy suggesting an interaction between these factors. Moreover, these results provide an explanation for the controversial findings obtained when analysing the effect of any single one of these factors on the appearance of T1D-associated autoimmunity. Copyright © 2011 John Wiley & Sons, Ltd.

The economically important edible basidiomycete mushroom Agaricus bisporus thrives ondecaying plant material in forests and grasslands of North America and Europe. It degrades forestlitter and contributes to global carbon recycling, depolymerizing (hemi-)cellulose and lignin in plantbiomass. Relatively little is known about how A. bisporus degrades compost in the controlledenvironment in commercial production facilities and utilizes this substrate to produce mushrooms.Using transcriptomics and proteomics linked to analysis of the compositional changes in thecompost, we showed that changes in plant biomass degradation by A. bisporus occur throughout itslife cycle. Lignin degradation appears to only occur during the spawning stage. In contrast, (hemi-)cellulolytic genes were highly expressed at the first flush, whereas low expression was observed atthe second flush. The essential role for many highly expressed plant biomass degrading genes wassupported by exo-proteome analysis, demonstrating the presence of these enzymes during specificstages. The out-of-phase enzyme production in the second flush may explain the reduction in the number of mushrooms during the second flush.Combined with other data generated in our lab we have now generated the first detailed model ofthe genes and enzymes involved in compost degradation and utilization by A. bisporus, which hasprovided many leads for a better understanding and improvement of the commercial mushroomcultivation.

Genetic heterogeneity may affect the analysis of risk factors associated with type 1 diabetes (T1D). We studied the effect of the INS -23A/T, PTPN22 1858C/T, and CTLA-4 +49A/G polymorphisms on the emergence of T1D-associated autoimmunity in children exposed to cow's milk (CM) based formula during early or late infancy. The study comprised of 156 children from the Finnish DIPP cohort who had developed >or= 2 types of autoantibodies (ICA, IAA, GADA or IA-2A) or clinical T1D and 563 control children. The PTPN22 1858T allele was associated with the appearance of the autoantibodies and clinical T1D among children exposed to CM formula before the age of 6 months (PTPN22: for all P

Basidiomycetous white-rot fungi are the only organisms that can efficiently decompose all the components of wood. Moreover, white-rot fungi possess the ability to mineralize recalcitrant lignin polymer with their extracellular, oxidative lignin-modifying enzymes (LMEs), i.e. laccase, lignin peroxidase (LiP), manganese peroxidase (MnP), and versatile peroxidase (VP). Within one white-rot fungal species LMEs are typically present as several isozymes encoded by multiple genes. This study focused on two effi cient lignin-degrading white-rot fungal species, Phlebia radiata and Dichomitus squalens. Molecular level knowledge of the LMEs of the Finnish isolate P. radiata FBCC43 (79, ATCC 64658) was complemented with cloning and characterization of a new laccase (Pr-lac2), two new LiP-encoding genes (Pr-lip1, Pr-lip4), and Pr-lip3 gene that has been previously described only at cDNAlevel. Also, two laccase-encoding genes (Ds-lac3, Ds-lac4) of D. squalens were cloned and characterized for the first time. Phylogenetic analysis revealed close evolutionary relationships between the P. radiata LiP isozymes. Distinct protein phylogeny for both P. radiata and D. squalens laccases suggested different physiological functions for the corresponding enzymes. Supplementation of P. radiata liquid culture medium with excess Cu2+ notably increased laccase activity and good fungal growth was achieved in complex medium rich with organic nitrogen. Wood is the natural substrate of lignin-degrading white-rot fungi, supporting production of enzymes and metabolites needed for fungal growth and the breakdown of lignocellulose. In this work, emphasis was on solid-state wood or wood-containing cultures that mimic the natural growth conditions of white-rot fungi. Transcript analyses showed that wood promoted expression of all the presently known LME-encoding genes of P. radiata and laccase-encoding genes of D. squalens. Expression of the studied individual LME-encoding genes of P. radiata and D. squalens was unequal in transcript quantities and apparently time-dependent, thus suggesting the importance of several distinct LMEs within one fungal species. In addition to LMEs, white-rot fungi secrete other compounds that are important in decomposition of wood and lignin. One of these compounds is oxalic acid, which is a common metabolite of wood-rotting fungi. Fungi produce also oxalic-acid degrading enzymes of which the most widespread is oxalate decarboxylase (ODC). However, the role of ODC in fungi is still ambiguous with propositions from regulation of intra and extracellular oxalic acid levels to a function in primary growth and concomitant production of ATP. In this study, intracellular ODC activity was detected in four white-rot fungal species, and D. squalens showed the highest ODC activity upon exposure to oxalic acid. Oxalic acid was the most common organic acid secreted by the ODC-positive white-rot fungi and the only organic acid detected in wood cultures. The ODC-encoding gene Ds-odc was cloned from two strains of D. squalens showing the first characterization of an odc-gene from a white-rot polypore species. Biochemical properties of the D. squalens ODC resembled those described for other basidiomycete ODCs. However, the translated amino acid sequence of Ds-odc has a novel N-terminal primary structure with a repetitive Ala-Ser-rich region of ca 60 amino acid residues in length. Expression of the Ds-odc transcripts suggested a constitutive metabolic role for the corresponding ODC enzyme. According to the results, it is proposed that ODC may have an essential implication for the growth and basic metabolism of wood-decaying fungi. Kantasieniin kuuluvat valkolahosienet ovat ainoita organismeja, jotka hajottavat tehokkaasti puun kaikkia komponentteja. Tämän lisäksi ne pystyvät mineralisoimaan vaikeasti hajoavaa ligniinipolymeeriä solujensa ulkopuolelle erittyvien, hapettavien ligniiniä muokkaavia entsyymien avulla. Näitä entsyymejä, joista valkolahosienet tuottavat tyypillisesti useita eri geenien koodaamia isoentsyymejä, ovat lakkaasi, ligniiniperoksidaasi (LiP), mangaaniperoksidaasi (MnP) ja versatiiliperoksidaasi (VP). -- Tässä tutkimuksessa keskityttiin kahteen ligniiniä tehokkaasti hajottavaan valkolahosieneen: rusorypykkään (Phlebia radiata) ja salokääpään (Dichomitus squalens). Molekyylitason tietoa Suomesta eristetyn P. radiata FBCC43 (79, ATCC 64658) sienen ligniiniä muokkaavista entsyymeistä täydennettiin kloonaamalla ja karakterisoimalla yksi lakkaasi (Pr-lac2) ja kolme lip-geeniä (Pr-lip1, Pr-lip3, Prlip4), joista vain Pr-lip3 on aiemmin kloonattu cDNA:sta. D. squalensista kloonattiin ja karakterisoitiin ensimmäisen kerran kaksi lakkaasigeeniä (Ds-lac3, Ds-lac4). Fylogeneettinen analyysi osoitti P. radiatan LiP-isoentsyymien olevan evolutiivisesti hyvin lähellä toisiaan. P. radiatan ja D. squalensin lakkaasit ovat puolestaan kaukaista sukua toisilleen, joten ne saattavat osallistua erilaisiin fysiologisiin toimintoihin. Lakkaasiaktiivisuus nousi huomattavasti, kun P. radiatan liemiviljelmiin lisättiin ylimäärin Cu2+-ioneja. Sieni kasvoi hyvin ravinteikkaissa, runsaasti orgaanista typpeä sisältävissä liemiviljelmissä. Puu on valkolahosienten luonnollinen kasvualusta, jolla sienet tuottavat kasvuunsa ja lignoselluloosan hajottamiseen tarvittavia entsyymejä ja aineenvaihduntatuotteita. Tässä työssä valkolahosieniä kasvatettiin puulla ja puuta sisältävillä, luonnollisia kasvuolosuhteita jäljittelevillä alustoilla. Transkriptianalyysit osoittivat kaikkien P. radiatan tunnettujen ligniiniä muokkaavia entsyymien ja D. squalensin lakkaasien ilmentyvän sienten kasvaessa puulla. Yksittäisten P. radiatan lip- ja lakkaasigeenien sekä D. squalensin lakkaasigeenien transkriptimäärissä oli eroja kasvun aikana. Näiden tulosten perusteella useilla ligniiniä muokkaavilla isoentsyymeillä on tärkeä merkitys valkolahosienten kasvaessa puulla. Entsyymien lisäksi valkolahosienet erittävät puun ja ligniinin hajotukseen osallistuvia yhdisteitä, kuten oksaalihappoa, joka on puuta lahottavien sienten yleinen aineenvaihduntatuote. Sienet tuottavat myös oksaalihappoa hajottavia entsyymejä, joista yleisin on oksalaattidekarboksylaasi (ODC). ODC:n merkitystä sienissä ei toistaiseksi tunneta tarkasti. Entsyymin on ehdotettu säätelevän solunsisäistä ja -ulkoista oksaalihappopitoisuutta sekä osallistuvan ATP:n tuottoon. Tässä tutkimuksessa solunsisäistä ODC-aktiivisuutta havaittiin neljällä uudella valkolahosienikannalla. Korkein ODC-aktiivisuus mitattiin D. squalensilla kasvualustoihin tehdyn oksaalihappolisäyksen jälkeen. Oksaalihappo oli ODC:a tuottavien sienten yleisimmin erittämä ja ainoa puualustalla havaittu orgaaninen happo. Työssä kahdesta D. squalens kannasta kloonattu odc-geeni on ensimmäinen valkolahottajakäävästä kuvattu odc-geeni. D. squalensin ODC oli biokemiallisilta ominaisuuksiltaan samankaltainen muista kantasienistä kuvattujen ODC-proteiinien kanssa. Ds-odc -geenistä käännetyn aminohapposekvenssin mukaan sen koodaaman proteiinin N-terminaalissa on kuitenkin uudenlainen, noin 60 aminohapon pituinen paljon alaniinia ja seriiniä sisältävä toistojakso. Ds-odc geenin ilmentymisen perusteella sen koodaamaa entsyymiä tuotetaan konstitutiivisesti. ODC saattaakin olla tärkeä entsyymi puuta lahottavien sienten kasvulle ja perusaineenvaihdunnalle.