| a preliminary survey of cycloheximide-resistant airborne fungi in turin, italy. | numbers and type of the cycloheximide-resistant part of the aerially transmitted mycoflora of turin were studied. samples from three areas characterized by differing human usage were taken in the first week of march. during each sampling, 12 m3 of air were aspirated, using an one-stage volumetric sieve sampler. fifty-two mesophilic species and eight thermotolerant were isolated. propagule load varied from 2.92 to 120.31 cfu m-3. the following species appear not to have been reported previously f ... | 1993 | 8247094 |
| suppressive subtractive hybridization and differential screening identified genes differentially expressed in yeast and mycelial forms of ophiostoma piceae. | ophiostoma piceae is a sap-staining fungus that colonizes and discolours wood. it has been established that the mycelium form but not the yeast form becomes pigmented in vitro. suppressive subtractive hybridization pcr was used to isolate transcripts specifically upregulated in either the yeast or mycelial forms of o. piceae. subtracted cdnas were cloned and transformed into escherichia coli. the yeast and mycelium specific clones were then screened by differential screening to reduce the possib ... | 2004 | 15336419 |
| fatal ophiostoma piceae infection in a patient with acute lymphoblastic leukaemia. | we report to our knowledge the first case of human infection with ophiostoma piceae. this sporothrix schenckii-related fungus caused disseminated infection involving the lung and the brain in a patient with lymphoblastic lymphoma. the case emphasizes the significance of molecular techniques for identification of rare fungi in the clinical microbiology laboratory. | 2009 | 19208892 |
| analysis of the distribution and regulation of three representative subtilase genes in sapstaining fungi. | in order to grow in wood, sapstaining fungi produce multiple proteases. previously we have shown that three groups of subtilases appear to be present in sapstaining fungi; however, it is unknown whether these groups have distinct physiological roles. a representative gene from each of the three groups was chosen and the copy number and presence of homologous genes in other sapstaining fungi were determined. as well, the expressional regulation of these genes was determined in response to availab ... | 2004 | 14732272 |
| transforming the sapstaining fungus ophiostoma piceae with agrobacterium tumefaciens. | a transformation protocol mediated by agrobacterium tumefaciens is described for the sapstaining fungus ophiostoma piceae. we compared transformants obtained from agrobacterium with those obtained from yeast-like cells made into spheroplasts and treated with cacl2. for all putative transformants analyzed, southern hybridization confirmed that the hygromycin resistance gene had been integrated into the genomic dna. while all transformants obtained from the treated spheroplasts had multiple copy v ... | 2003 | 12897840 |
| the ophiostoma piceae complex in the southern hemisphere: a phylogenetic study. | the ophiostoma piceae species complex incorporates several economically important species, including serious tree pathogens and agents of bluestain. the species in the complex are morphologically similar, but can be distinguished from each other based on morphology, biology, mating type studies and molecular data. at present, all the species in the complex are considered to be native to the northern hemisphere, most of them with a very wide distribution. only a few sporadic reports of members of ... | 2003 | 12825520 |
| production, isolation and characterization of a sterol esterase from ophiostoma piceae. | we studied extracellular sterol esterase production by the ascomycete ophiostoma piceae in liquid culture. esterase activity was found in low levels in glucose medium but it was strongly induced by olive oil. an esterase was purified from the 0.5% olive oil-supplemented cultures using ultrafiltration followed by a single chromatographic step on a hydrophobic interaction column. the enzyme was a glycoprotein with 8% n-linked carbohydrate content, a molecular mass by sds/page around 56.5 kda and a ... | 2002 | 12479402 |
| multigene phylogenies and morphological characterization of five new ophiostoma spp. associated with spruce-infesting bark beetles in china. | ophiostoma spp. (ophiostomatales, ascomycota) are well-known fungi associated with bark beetles (coleoptera: scolytinae). some of these are serious tree pathogens, while the majority is blue-stain agents of timber. in recent years, various bark beetle species have been attacking spruce forests in qinghai province, china, causing significant damage. a preliminary survey was done to explore the diversity of the ophiostomatoid fungal associates of these beetles. the aims of the present study were t ... | 2016 | 27020148 |
| green synthesis of β-sitostanol esters catalyzed by the versatile lipase/sterol esterase from ophiostoma piceae. | β-sitostanol esters, used as dietary complement for decreasing cholesterol absorption, have been synthesized at 28°c via direct esterification or transesterification catalyzed by the versatile lipase/sterol esterase from the ascomycete fungus o. piceae. direct esterification was conducted in biphasic isooctane: water systems containing 10mm β-sitostanol and lauric or oleic acid as acyl donors, reaching 90% esterification in 3h with the recombinant enzyme. the use of molar excesses of the free fa ... | 2017 | 27979115 |
| quorum-sensing mechanisms mediated by farnesol in ophiostoma piceae: effect on secretion of sterol esterase. | ophiostoma piceae cect 20416 is a dimorphic wood-staining fungus able to produce an extracellular sterol-esterase/lipase (ope) that is of great biotechnological interest. in this work, we have studied the morphological change of this fungus from yeast to hyphae, which is associated with the cell density-related mechanism known as quorum sensing (qs), and how this affects the secretion of ope. the data presented here confirm that the molecule e,e-farnesol accumulates as the cell number is growing ... | 2015 | 25888179 |
| production of a sterol esterase from ophiostoma piceae in batch and fed-batch bioprocesses using different pichia pastoris phenotypes as cell factory. | the potential biotechnological applications for the ophiostoma piceae sterol esterase (ope) are conditioned to the availability of high enzyme amounts at low prices. this enzyme is a versatile biocatalyst with different biotechnological applications. in this work a systematic study on its heterologous production in different pichia pastoris strains and operational strategies is presented. the best results were obtained using an aox1 defective yeast strain in a fed-batch bioprocess using methanol ... | 2014 | 24930588 |
| heterologous expression of a fungal sterol esterase/lipase in different hosts: effect on solubility, glycosylation and production. | ophiostoma piceae secretes a versatile sterol-esterase (ope) that shows high efficiency in both hydrolysis and synthesis of triglycerides and sterol esters. this enzyme produces aggregates in aqueous solutions, but the recombinant protein, expressed in komagataella (synonym pichia) pastoris, showed higher catalytic efficiency because of its higher solubility. this fact owes to a modification in the n-terminal sequence of the protein expressed in pichia pastoris, which incorporated 4-8 additional ... | 2015 | 25939548 |
| biotransformation of the trichoderma metabolite 6-n-pentyl-2h-pyran-2-one (6pap) by selected fungal isolates | a variety of fungi were tested for their ability to transform the antifungal trichoderma metabolite 6-n-pentyl-2h-pyran-2-one (6pap) (1). three penicillium isolates, a sclerotinia isolate, and a fusarium isolate were all able to rapidly metabolize 1 and gave mixtures of isomers of monohydroxylated 1 and, in some cases, products resulting from further oxidation to carboxylic acids. among these products were four previously unidentified metabolites (6, 7, 8, and 9) which were isolated and characte ... | 1999 | 10346944 |
| the genome and transcriptome of the pine saprophyte ophiostoma piceae, and a comparison with the bark beetle-associated pine pathogen grosmannia clavigera. | ophiostoma piceae is a wood-staining fungus that grows in the sapwood of conifer logs and lumber. we sequenced its genome and analyzed its transcriptomes under a range of growth conditions. a comparison with the genome and transcriptomes of the mountain pine beetle-associated pathogen grosmannia clavigera highlights differences between a pathogen that colonizes and kills living pine trees and a saprophyte that colonizes wood and the inner bark of dead trees. | 2013 | 23725015 |
| expression and properties of three novel fungal lipases/sterol esterases predicted in silico: comparison with other enzymes of the candida rugosa-like family. | lipases from the candida rugosa-like family are enzymes with great biotechnological interest. in a previous work, several enzymes from this family were identified by in silico mining of fungal genomes. here, we describe the cloning, expression, and characterization of putative lipases from the genomes of nectria haematococca, trichoderma reesei, and aspergillus niger and compared their catalytic properties with those of ope, a well-characterized sterol esterase/lipase from ophiostoma piceae. all ... | 2015 | 26272094 |
| diversity and pathogenicity of ophiostomatoid fungi associated with tetropium species colonizing picea abies in poland. | the ophiostomatoid fungi associated with cerambycid beetles tetropium spp. (their symbiotic vectors) colonizing norway spruce in poland (six species collected) were isolated. the virulence of representative isolates was evaluated through inoculations using 2-year-old norway spruce seedlings. a total of 1325 isolates (ophiostoma piceae, o. tetropii, o. minus, grosmannia piceiperda, g. cucullata, and five other less frequent taxa) were obtained. tetropium castaneum and t. fuscum were vectors of si ... | 2010 | 20490757 |
| study of a sterol esterase secreted by ophiostoma piceae: sequence, model and biochemical properties. | an extracellular sterol esterase from ophiostoma piceae efficiently hydrolyzes sterol esters, triglycerides and p-nitrophenol esters. cdna was screened with a probe obtained by pcr using as primers oligonucleotides corresponding to the n-terminal and internal mature enzyme sequences and complete sequence was obtained by 3' rapid amplification of cdna end (race) and inverse pcr. the o. piceae esterase gene had a length of 1.8 kbp and lacked introns. a search for proteins with related amino acid s ... | 2009 | 19281875 |
| a genomic comparison of putative pathogenicity-related gene families in five members of the ophiostomatales with different lifestyles. | ophiostomatoid fungi are vectored by their bark-beetle associates and colonize different host tree species. to survive and proliferate in the host, they have evolved mechanisms for detoxification and elimination of host defence compounds, efficient nutrient sequestration, and, in pathogenic species, virulence towards plants. here, we assembled a draft genome of the spruce pathogen ophiostoma bicolor. for our comparative and phylogenetic analyses, we mined the genomes of closely related species ( ... | 2017 | 28215351 |
| fungal genomes mining to discover novel sterol esterases and lipases as catalysts. | sterol esterases and lipases are enzymes able to efficiently catalyze synthesis and hydrolysis reactions of both sterol esters and triglycerides and due to their versatility could be widely used in different industrial applications. lipases with this ability have been reported in the yeast candida rugosa that secretes several extracellular enzymes with a high level of sequence identity, although different substrate specificity. this versatility has also been found in the sterol esterases from th ... | 2013 | 24138290 |
| genetic variability of canadian populations of the sapstain fungus ophiostoma piceae. | abstract genetic diversity was studied in seven canadian populations of ophiostoma piceae, the most prevalent sapstain fungus in canadian softwoods. a total of 239 single-spore isolates were recovered following a systematic survey of sapstain fungi in logs and lumber at seven selected sawmills in six canadian provinces (british columbia, alberta, saskatchewan, ontario, québec, and new brunswick). sampling was carried out on five commercially important softwood species: balsam fir (abies balsamea ... | 2001 | 18943849 |
| ophiostoma species (ascomycetes: ophiostomatales) associated with bark beetles (coleoptera: scolytinae) colonizing pinus radiata in northern spain. | bark beetles (coleoptera: scolytinae) are known to be associated with fungi, especially species of ophiostoma sensu lato and ceratocystis. however, very little is known about these fungi in spain. in this study, we examined the fungi associated with 13 bark beetle species and one weevil (coleoptera: entiminae) infesting pinus radiata in the basque country of northern spain. this study included an examination of 1323 bark beetles or their galleries in p. radiata. isolations yielded a total of 920 ... | 2007 | 17668036 |
| ophiostoma breviusculum sp. nov. (ophiostomatales, ascomycota) is a new species in the ophiostoma piceae complex associated with bark beetles infesting larch in japan. | a new species of the ophiostoma piceae-complex was isolated from bark beetles and the insect galleries of larix kaempferi in japan. this species was described as ophiostoma breviusculum. the fungus was morphologically similar to o. piceae and o. quercus. however the average length of the perithecial necks and synnemata were shorter than for o. piceae and o. quercus. synnemata morphological characteristics also differentiated o. breviusculum from the other species of the ophiostoma piceae-complex ... | 2006 | 17256583 |
| isolation of wood-inhabiting fungi from canadian hardwood logs. | wood-inhabiting fungi include many molds, wood-staining fungi, and decay fungi. most of these fungal species can result in economic losses to wood users. studies on molds, staining fungi, and decay fungi are necessary to be able to control their growth on wood and wood products. in this study, wood-inhabiting fungi were isolated from logs of 3 major canadian hardwood species: sugar maple, white birch, and yellow birch. two media were used for isolation. from these 3 wood species, a total of 1198 ... | 2005 | 15782228 |
| rapid detection of ophiostoma piceae and o. quercus in stained wood by pcr. | a rapid, sensitive, and simple method was developed to detect the sapstain fungi ophiostoma piceae and o. quercus in stained wood. by using microwave heating for dna extraction and pcr with internal transcribed spacer-derived-specific primers, detection was feasible within 4 h, even with dna obtained from a single synnema. this method can easily be extended for the detection of other wood-inhabiting fungi. | 1999 | 9872792 |
| isolation and characterization of a subtilisin-like serine proteinase secreted by the sap-staining fungus ophiostoma piceae. | identification of key enzymes of sapstain fungi which cause wood discoloration is necessary for targeted inhibition strategies. therefore proteinases involved in the nitrogen pathway have been characterized. the sap-staining fungus ophiostoma piceae strain 387n produced proteolytic enzymes when grown on wood and protein-supplemented media. proteolytic activity in culture filtrates was inhibited by pmsf and edta. the major protein in culture filtrates was a proteinase with a pi of 5.6 and a molec ... | 1996 | 8938373 |
| extracellular lipase production by a sapwood-staining fungus, ophiostoma piceae. | the extracellular lipase production of a sapwood-staining fungus, ophiostoma piceae, grown in liquid media, was optimally active at ph 5.5 and 37°c. although glucose, fructose, sucrose, starch and dextrin, as carbon sources for growth gave similar mycelial yields, which were higher than those obtained with arabinose, galactose or raffinose, the cells growing on those carbohydrates produced little extracellular lipase. however, both high biomass and lipase activity were obtained when plant oils ( ... | 1995 | 24415011 |
| factors affecting autolysis of a subtilisin-like serine proteinase secreted by ophiostoma piceae and identification of the cleavage site. | the extracellular serine proteinase secreted by ophiostoma piceae was degraded by autoproteolysis under certain conditions. at elevated temperatures the mature protein of 33 kda was rapidly degraded without any accumulation of protein breakdown products. glycerol, calcium ions and ammonium sulfate raised the heat stability of the enzyme, increasing its half-life at 45 degrees c from 1.9 min to 9.4 min, 40.4 min and 2 h, respectively. thermal unfolding of the proteinase also occurred at higher te ... | 1995 | 7654769 |
| on the variability of ophiostoma piceae. | the morphology and cultural characteristics of ophiostoma piceae were described on the basis of 22 strains from the cbs collection supplemented with 25 fresh isolates from poland, mostly from necrotic parts of quercus robur. the pleomorphism of anamorphs of the fungus is described in detail. the various cultural types could be reproduced by replicate transferance. the identity of the anamorph strains was confirmed using some strains that produced perithecia. it is concluded that cultures of o. p ... | 1989 | 2742373 |
| potential of ophiostoma piceae sterol esterase for biotechnologically relevant hydrolysis reactions. | the ascomycete ophiostoma piceae produces a sterol esterase (ope) with high affinity toward p-nitrophenol, glycerol, and sterol esters. recently, this enzyme has been heterologously expressed in the methylotrophic yeast pichia pastoris under the aox1 methanol-inducible promoter (paox1) using sorbitol as co-susbtrate, and the hydrolytic activity of the recombinant protein (ope*) turned out to be improved from a kinetic point of view. in this study, we analyze the effects of sorbitol during the ex ... | 2017 | 23138020 |
| recombinant sterol esterase from ophiostoma piceae: an improved biocatalyst expressed in pichia pastoris. | the ascomycete ophiostoma piceae produces a sterol esterase (ope) with high affinity towards p-nitrophenol, glycerol and sterol esters. its hydrolytic activity on natural mixtures of triglycerides and sterol esters has been proposed for pitch biocontrol in paper industry since these compounds produce important economic losses during paper pulp manufacture. | 2012 | 22676486 |
| characterization of the cleavage specificity of a subtilisin-like serine proteinase from ophiostoma piceae by liquid chromatography/mass spectrometry and tandem ms. | a proteinase secreted by the sapstaining fungus ophiostoma piceae is thought to be necessary for the primary retrieval of nitrogen from wood proteins. by using mass spectrometry (ms) techniques, we have established the cleavage specificity of this subtilisin-like serine proteinase. this work demonstrated the potential of ms in determining cleavage specificities of newly isolated proteinases in a relatively short time frame, and determined that the o. piceae proteinase showed a substrate specific ... | 1995 | 7589536 |
| crystal structures of ophiostoma piceae sterol esterase: structural insights into activation mechanism and product release. | sterol esterases are able to efficiently hydrolyze both sterol esters and triglycerides and to carry out synthesis reactions in the presence of organic solvents. their high versatility makes them excellent candidates for biotechnological purposes. sterol esterase from fungus ophiostoma piceae (ope) belongs to the family abh03.01 of the candida rugosa lipase-like proteins. crystal structures of ope were solved in this study for the closed and open conformations. enzyme activation involves a large ... | 2014 | 25108239 |
| pathogenicity of four blue-stain fungi associated with aggressive and nonaggressive bark beetles. | abstract the pathogenicity of two isolates of each of four bark beetle-associated blue-stain fungi was evaluated after mass inoculation of about 40-year-old norway spruce trees (picea abies). trees were inoculated with a different isolate of each fungus in 1995 and 1996 at a density of 400 inoculations per m(2) in a 1.2-m-wide band on the lower bole (about 270 inoculations per tree). trees were felled 15 weeks after inoculation. in 1995, ceratocystis polonica was the only fungus that had stained ... | 1998 | 18944997 |
| identifying pigmentation-related genes in ophiostoma piceae using agrobacterium-mediated integration. | abstract wood sapstain, a cosmetic defect that results in significant economical loss to forest-products industries, is caused by mycelial melanization of the wood-colonizing ophiostomatoid fungi. to improve our understanding of how melanin biosynthesis is regulated in the cosmopolitan sapstaining fungus, ophiostoma piceae, we used insertional mutagenesis. insertional mutants were generated by restriction enzyme-mediated integration (remi) and agrobacterium-mediated integration (ami). we screene ... | 2007 | 18944168 |