| a matter of scale and dimensions: chromatin of chromosome landmarks in the fungi. | chromatin and chromosomes of fungi are highly diverse and dynamic, even within species. much of what we know about histone modification enzymes, rna interference, dna methylation, and cell cycle control was first addressed in saccharomyces cerevisiae, schizosaccharomyces pombe, aspergillus nidulans, and neurospora crassa. here, we examine the three landmark regions that are required for maintenance of stable chromosomes and their faithful inheritance, namely, origins of dna replication, telomere ... | 2017 | 28752814 |
| mitotic nuclear pore complex segregation involves nup2 in aspergillus nidulans. | transport through nuclear pore complexes (npcs) during interphase is facilitated by the nucleoporin nup2 via its importin α- and ran-binding domains. however, aspergillus nidulans and vertebrate nup2 also locate to chromatin during mitosis, suggestive of mitotic functions. in this study, we report that nup2 is required for mitotic npc inheritance in a. nidulans interestingly, the role of nup2 during mitotic npc segregation is independent of its importin α- and ran-binding domains but relies on a ... | 2017 | 28747316 |
| defensive repertoire of drosophila larvae in response to toxic fungi. | chemical warfare including insecticidal secondary metabolites is a well-known strategy for environmental microbes to monopolize a food source. insects in turn have evolved behavioural and physiological defences to eradicate or neutralize the harmful microorganisms. we studied the defensive repertoire of insects in this interference competition by combining behavioural and developmental assays with whole-transcriptome time-series analysis. confrontation with the toxic filamentous fungus aspergill ... | 2017 | 28746736 |
| prevention of melanin formation during aryl alcohol oxidase production under growth-limited conditions using an aspergillus nidulans cell factory. | an aspergillus nidulans cell factory was genetically engineered to produce an aryl alcohol oxidase (aao). the cell factory initiated production of melanin when growth-limited conditions were established using stationary plates and shaken flasks. this phenomenon was more pronounced when the strain was cultured in a trickle bed reactor (tbr). this study investigated different approaches to reduce melanin formation in fungal mycelia and liquid medium in order to increase the enzyme production yield ... | 2017 | 28738504 |
| deletion of the cela gene in aspergillus nidulans triggers overexpression of secondary metabolite biosynthetic genes. | although much progress has been made in the study of cell wall biosynthetic genes in the model filamentous fungus aspergillus nidulans, there are still targets awaiting characterization. an example is the gene cela (ania_08444) encoding a putative mixed linkage glucan synthase. to characterize the role of cela, we deleted it in a. nidulans, analyzed the phenotype of the mycelium and performed rna-seq. the strain shows a very strong phenotype, namely "balloons" along the hyphae and aberrant conid ... | 2017 | 28729615 |
| a robust high-throughput fungal biosensor assay for the detection of estrogen activity. | estrogenic active compounds are present in a variety of sources and may alter biological functions in vertebrates. therefore, it is crucial to develop innovative analytical systems that allow us to screen a broad spectrum of matrices and deliver fast and reliable results. we present the adaptation and validation of a fungal biosensor for the detection of estrogen activity in cow derived samples and tested the clinical applicability for pregnancy diagnosis in 140 mares and 120 cows. as biosensor ... | 2017 | 28712952 |
| steroid 11-alpha-hydroxylation by the fungi aspergillus nidulans and aspergillus ochraceus. | steroids are a group of natural compounds derived from the cyclopentane-perhydro-phenantrene nucleus that have a great interest for the pharmaceutical industries as a consequence of their physiological effects. among their functions are anti-inflammatory, immunosuppressive, or contraceptive activities. nowadays, microbial transformation of steroid precursors is winning relevance opposite to the chemical synthesis, since it allows for decreasing time, expenses, and environmental pollution. pharma ... | 2017 | 28710635 |
| the gata-type transcription factor csm1 regulates conidiation and secondary metabolism in fusarium fujikuroi. | gata-type transcription factors (tfs) such as the nitrogen regulators area and areb, or the light-responsive tfs wc-1 and wc-2, play global roles in fungal growth and development. the conserved gata tf nsdd is known as an activator of sexual development and key repressor of conidiation in aspergillus nidulans, and as light-regulated repressor of macroconidia formation in botrytis cinerea. in the present study, we functionally characterized the nsdd ortholog in fusarium fujikuroi, named csm1. del ... | 2017 | 28694801 |
| sirtuin a regulates secondary metabolite production by aspergillus nidulans. | late-stage cultures of filamentous fungi under nutrient starvation produce valuable secondary metabolites such as pharmaceuticals and pigments, as well as deleterious mycotoxins, all of which have remarkable structural diversity and wide-spectrum bioactivity. the fungal mechanisms regulating the synthesis of many of these compounds are not fully understood, but sirtuin a (sira) is a key factor that initiates production of the secondary metabolites, sterigmatocystin and penicillin g, by aspergill ... | 2017 | 28674377 |
| the aspergillus nidulans velvet-interacting protein, vipa, is involved in light-stimulated heme biosynthesis. | filamentous fungi are able to differentiate morphologically and adapt the metabolism to internal and external cues. one major regulator is the so-called velvet protein, vea, best studied in aspergillus nidulans. the protein interacts with several other proteins to regulate light sensing, the balance between asexual and sexual development, penicillin biosynthesis or mycotoxin production. here, we characterized a novel vea-interacting protein, vipa. the 334 amino acid long protein comprises a far1 ... | 2017 | 28657694 |
| copper resistance in aspergillus nidulans relies on the pi-type atpase crpa, regulated by the transcription factor acea. | copper homeostasis has been extensively studied in mammals, bacteria, and yeast, but it has not been well-documented in filamentous fungi. in this report, we investigated the basis of copper tolerance in the model fungus aspergillus nidulans. three genes involved in copper homeostasis have been characterized. first, crpa the a. nidulans ortholog of candida albicans cacrp1 gene encoding a pi-type atpase was identified. the phenotype of crpa deletion led to a severe sensitivity to cu(+2) toxicity ... | 2017 | 28611736 |
| identification and heterologous production of a benzoyl-primed tricarboxylic acid polyketide intermediate from the zaragozic acid a biosynthetic pathway. | zaragozic acid a (1) is a potent cholesterol lowering, polyketide natural product made by various filamentous fungi. the reconstitution of enzymes responsible for the initial steps of the biosynthetic pathway of 1 is accomplished using an engineered fungal heterologous host. these initial steps feature the priming of a benzoic acid starter unit onto a highly reducing polyketide synthase (hrpks), followed by oxaloacetate extension and product release to generate a tricarboxylic acid containing pr ... | 2017 | 28605916 |
| a scalable platform to identify fungal secondary metabolites and their gene clusters. | the genomes of filamentous fungi contain up to 90 biosynthetic gene clusters (bgcs) encoding diverse secondary metabolites-an enormous reservoir of untapped chemical potential. however, the recalcitrant genetics, cryptic expression, and unculturability of these fungi prevent scientists from systematically exploiting these gene clusters and harvesting their products. as heterologous expression of fungal bgcs is largely limited to the expression of single or partial clusters, we established a scal ... | 2017 | 28604695 |
| a mechanism for a single nucleotide intron shift. | spliceosomal introns can occupy nearby rather than identical positions in orthologous genes (intron sliding or shifting). stwintrons are complex intervening sequences, where an 'internal' intron interrupts one of the sequences essential for splicing, generating after its excision, a newly formed canonical intron defined as 'external'. in one experimentally demonstrated configuration, two alternatively excised internal introns, overlapping by one g, disrupt respectively the donor and the acceptor ... | 2017 | 28595329 |
| expression system for heterologous protein expression in the filamentous fungus aspergillus unguis. | heterologous protein expression in filamentous fungi is advantageous, especially in the context of large scale production of high volume low value recombinant proteins. however, such systems are rare and not available in public domain. a novel filamentous fungus - aspergillus unguis nii 08123 was used as host for developing a protein expression system. an expression cassette was assembled using a. nidulans glyceraldehyde 3 phosphate dehydrogenase promoter (pgapd), tryptophan synthase transcripti ... | 2017 | 28578805 |
| cop9 signalosome subunit pfcsne regulates secondary metabolism and conidial formation in pestalotiopsis fici. | the cop9 signalosome (csn) is a highly conserved multiprotein complex in all eukaryotes and involved in regulation of organism development. in filamentous fungi, several lines of evidence indicate that fungal development and secondary metabolism (sm) are mediated by the fifth subunit of csn, called csne. here we uncover a connection with csne and conidial formation as well as sm regulation in the plant endophytic fungus pestalotiopsis fici. a homology search of the p. fici genome with csne, invo ... | 2017 | 28550524 |
| the lectin chaperone calnexin is involved in the endoplasmic reticulum stress response by regulating ca(2+) homeostasis in aspergillus nidulans. | the ca(2+)-mediated signaling pathway is crucial for environmental adaptation in fungi. here we show that calnexin, a molecular chaperone located in the endoplasmic reticulum (er), plays an important role in regulating the cytosolic free calcium concentration ([ca(2+)]c) in aspergillus nidulans inactivation of calnexin (clxa) in a. nidulans caused severe defects in hyphal growth and conidiation under er stress caused by the er stress-inducing agent dithiothreitol (dtt) or high temperature. impor ... | 2017 | 28550061 |
| erratum: differential control of asexual development and sterigmatocystin biosynthesis by a novel regulator in aspergillus nidulans. | | 2017 | 28548131 |
| a cryptic pigment biosynthetic pathway uncovered by heterologous expression is essential for conidial development in pestalotiopsis fici. | spore pigmentation is very common in the fungal kingdom. the best studied pigment in fungi is melanin which coats the surface of single cell spores. what and how pigments function in a fungal species with multiple cell conidia is poorly understood. here, we identified and deleted a polyketide synthase (pks) gene pfmae and showed that it is essential for multicellular conidial pigmentation and development in a plant endophytic fungus, pestalotiopsis fici. to further characterize the melanin pathw ... | 2017 | 28517364 |
| nmea, a novel efflux transporter specific for nucleobases and nucleosides, contributes to metal resistance in aspergillus nidulans. | through minos transposon mutagenesis we obtained a. nidulans mutants resistant to 5-fluorouracil due to insertions into the upstream region of the uncharacterized gene nmea, encoding a major facilitator superfamily (mfs) transporter. minos transpositions increased nmea transcription, which is otherwise extremely low under all conditions tested. to dissect the function of nmea we used strains overexpressing or genetically lacking the nmea gene. strains overexpressing nmea are resistant to toxic p ... | 2017 | 28509393 |
| pulses of ca(2+) coordinate actin assembly and exocytosis for stepwise cell extension. | many eukaryotic cells grow by extending their cell periphery in pulses. the molecular mechanisms underlying this process are not yet fully understood. here we present a comprehensive model of stepwise cell extension by using the unique tip growth system of filamentous fungi. live-cell imaging analysis, including superresolution microscopy, revealed that the fungus aspergillus nidulans extends the hyphal tip in an oscillatory manner. the amount of f-actin and secretory vesicles (sv) accumulating ... | 2017 | 28507141 |
| structure and function of a broad-specificity chitin deacetylase from aspergillus nidulans fgsc a4. | enzymatic conversion of chitin, a β-1,4 linked polymer of n-acetylglucosamine, is of major interest in areas varying from the biorefining of chitin-rich waste streams to understanding how medically relevant fungi remodel their chitin-containing cell walls. although numerous chitinolytic enzymes have been studied in detail, relatively little is known about enzymes capable of deacetylating chitin. we describe the structural and functional characterization of a 237 residue deacetylase (ancda) from ... | 2017 | 28496100 |
| the role of vosa/velb-activated developmental gene vada in aspergillus nidulans. | the filamentous fungus aspergillus nidulans primarily reproduces by forming asexual spores called conidia, the integrity of which is governed by the nf-κb type velvet regulators vosa and velb. the vosa-velb hetero-complex regulates the expression of spore-specific structural and regulatory genes during conidiogenesis. here, we characterize one of the vosa/velb-activated developmental genes, called vada, the expression of which in conidia requires activity of both vosa and velb. vada (an5709) is ... | 2017 | 28481894 |
| sirtuin e is a fungal global transcriptional regulator that determines the transition from the primary growth to the stationary phase. | in response to limited nutrients, fungal cells exit the primary growth phase, enter the stationary phase, and cease proliferation. although fundamental to microbial physiology in many environments, the regulation of this transition is poorly understood but likely involves many transcriptional regulators. these may include the sirtuins, which deacetylate acetyllysine residues of histones and epigenetically regulate global transcription. therefore, we investigated the role of a nuclear sirtuin, si ... | 2017 | 28465348 |
| conservation and diversity of the regulators of cellulolytic enzyme genes in ascomycete fungi. | in the past decade, various transcriptional activators of cellulolytic enzyme genes have been identified in ascomycete fungi. the regulatory system of cellulolytic enzymes is not only partially conserved, but also significantly diverse. for example, trichoderma reesei has a system distinct from those of aspergillus and neurospora crassa-the former utilizes xyr1 (the aspergillus xlnr ortholog) as the major regulator of cellulolytic enzyme genes, while the latter uses clr-2/clrb/manr orthologs. xl ... | 2017 | 28451846 |
| napa mediates a redox regulation of the antioxidant response, carbon utilization and development in aspergillus nidulans. | the redox-regulated transcription factors (tfs) of the bzip ap1 family, such as yeast yap1 and fission yeast pap1, are activated by peroxiredoxin proteins (prxs) to regulate the antioxidant response. previously, aspergillus nidulans mutants lacking the yap1 ortholog napa have been characterized as sensitive to h2o2 and menadione. here we study napa roles in relation to tfs srra and atfa, also involved in oxidant detoxification, showing that these tfs play different roles in oxidative stress resi ... | 2017 | 28424666 |
| interrelationships of vel1 and env1 in light response and development in trichoderma reesei. | sexual development is regulated by a complex regulatory mechanism in fungi. for trichoderma reesei, the light response pathway was shown to impact sexual development, particularly through the photoreceptor envoy. moreover, t. reesei communicates chemically with a potential mating partner in its vicinity, a response which is mediated by the velvet family protein vel1 and its impact on secondary metabolism. we therefore studied the regulatory interactions of env1 and vel1 with a focus on sexual de ... | 2017 | 28423024 |
| differential control of asexual development and sterigmatocystin biosynthesis by a novel regulator in aspergillus nidulans. | the filamentous fungus aspergillus nidulans primarily reproduces by forming asexual spores called conidia and produces the mycotoxin sterigmatocystin (st), the penultimate precursor of aflatoxins. it has been known that asexual development and st production are tightly co-regulated by various regulatory inputs. here, we report that the novel regulator asla with a c2h2 domain oppositely regulates development and st biosynthesis. nullifying asla resulted in defective conidiation and reduced expres ... | 2017 | 28422127 |
| comparative transcriptome sequence analysis of sporulation-related genes of aspergillus cristatus in response to low and high osmolarity. | aspergillus cristatus undergoes sexual and asexual development under conditions of low and high osmotic pressure, respectively. in this study, the expression levels of 107 genes associated with sexual and asexual development were analysed under conditions of low and high osmotic pressure by rna sequencing. the results showed that 37 genes were up-regulated and other genes were down-regulated under conditions of high osmotic pressure, with most of the up-regulated genes associated with asexual de ... | 2017 | 28417188 |
| involvement of a velvet protein clvelb in the regulation of vegetative differentiation, oxidative stress response, secondary metabolism, and virulence in curvularia lunata. | the ortholog of aspergillus nidulans velb, which is known as clvelb, was studied to gain a broader insight into the functions of a velvet protein in curvularia lunata. with the expected common and specific functions of clvelb, the deletion of clvelb results in similar though not identical phenotypes. the pathogenicity assays revealed that δclvelb was impaired in colonizing the host tissue, which corresponds to the finding that clvelb controls the production of conidia and the methyl 5-(hydroxyme ... | 2017 | 28393907 |
| laea negatively regulates dothistromin production in the pine needle pathogen dothistroma septosporum. | in filamentous fungi both pathway-specific and global regulators regulate genes involved in the biosynthesis of secondary metabolites. laea is a global regulator that was named for its mutant phenotype, loss of aflr expression, due to its effect on the aflatoxin-pathway regulator aflr in aspergillus spp. the pine needle pathogen dothistroma septosporum produces a polyketide virulence factor, dothistromin, that is chemically related to aflatoxin and whose pathway genes are also regulated by an or ... | 2016 | 27818262 |
| comparative genomic and transcriptomic analyses of the fuzhuan brick tea-fermentation fungus aspergillus cristatus. | aspergillus cristatus is the dominant fungus involved in the fermentation of chinese fuzhuan brick tea. aspergillus cristatus is a homothallic fungus that undergoes a sexual stage without asexual conidiation when cultured in hypotonic medium. the asexual stage is induced by a high salt concentration, which completely inhibits sexual development. the taxon is therefore appropriate for investigating the mechanisms of asexual and sexual reproduction in fungi. in this study, de novo genome sequencin ... | 2016 | 27267057 |
| diversity, molecular phylogeny and fingerprint profiles of airborne aspergillus species using random amplified polymorphic dna. | in the present study, diversity and phylogenetic relationship of aspergillus species isolated from tehran air was studied using random amplified polymorphic dna (rapd)-polymerase chain reaction (rapd-pcr). thirty-eight aspergillus isolates belonging to 12 species i.e. a. niger (28.94 %, 11 isolates), a. flavus (18.42 %, 7 isolates), a. tubingensis (13.15 %, 5 isolates), a. japonicus (10.52 %, 4 isolates), a. ochraceus (10.52 %, 4 isolates), and 2.63 %, 1 isolate from each a. nidulans, a. amstelo ... | 2016 | 27116962 |
| investigation of a 6-msa synthase gene cluster in aspergillus aculeatus reveals 6-msa-derived aculinic acid, aculins a-b and epi-aculin a. | aspergillus aculeatus, a filamentous fungus belonging to the aspergillus clade nigri, is an industrial workhorse in enzyme production. recently we reported a number of secondary metabolites from this fungus; however, its genetic potential for the production of secondary metabolites is vast. in this study we identified a 6-methylsalicylic acid (6-msa) synthase from a. aculeatus, and verified its functionality by episomal expression in a. aculeatus and heterologous expression in a. nidulans. feedi ... | 2015 | 26374386 |
| examining the evolution of the regulatory circuit controlling secondary metabolism and development in the fungal genus aspergillus. | filamentous fungi produce diverse secondary metabolites (sms) essential to their ecology and adaptation. although each sm is typically produced by only a handful of species, global sm production is governed by widely conserved transcriptional regulators in conjunction with other cellular processes, such as development. we examined the interplay between the taxonomic narrowness of sm distribution and the broad conservation of global regulation of sm and development in aspergillus, a diverse funga ... | 2015 | 25786130 |
| (1→3)-α-d-glucans from aspergillus spp.: structural characterization and biological study on their carboxymethylated derivatives. | alkali-soluble polysaccharides (asps) were isolated from the cell wall of four aspergillus species (a. fumigatus, a. nidulans, a. niger, and a. wentii). the chemical and spectroscopic investigations (immunofluorescent labelling, composition analysis, methylation analysis, ftir, and 1h nmr) indicated that the asps were polymers composed almost exclusively of (1→3)-linked α-d-glucose. after carboxymethylation (cm), the activity of (1→3)-α-d-glucans on three human cell lines (hsf, hela, and jurkat) ... | 2015 | 25601326 |
| development of rflp-pcr method for the identification of medically important aspergillus species using single restriction enzyme mwoi. | in this study we attempted to modify the pcr-rflp method using restriction enzyme mwoi for the identification of medically important aspergillus species. our subjects included nine standard aspergillus species and 205 aspergillus isolates of approved hospital acquired infections and hospital indoor sources. first of all, aspergillus isolates were identified in the level of species by using morphologic method. a twenty four hours culture was performed for each isolates to harvest aspergillus myce ... | 2014 | 25242934 |
| topical application of preparations containing dna repair enzymes prevents ultraviolet-induced telomere shortening and c-fos proto-oncogene hyperexpression in human skin: an experimental pilot study. | the exposure to ultraviolet radiation (uvr) is one of the most important risk factors for skin aging and increases the risk of malignant transformation. telomere shortening and an altered expression of the proto-oncogene c-fos are among the key molecular mechanisms associated with photoaging and tumorigenesis. photolyase from a. nidulans and endonuclease from m. luteus are xenogenic dna repair enzymes which can reverse the molecular events associated with skin aging and carcinogenosis caused by ... | 2013 | 24002149 |
| engineering fungal nonreducing polyketide synthase by heterologous expression and domain swapping. | we reannotated the a. niger nr-pks gene, e_gw1_19.204, and its downstream r domain gene, est_gwplus_c_190476, as a single gene which we named dtba. heterologous expression of dtba in a. nidulans demonstrated that dtba protein produces two polyketides, 2,4-dihydroxy-3,5,6-trimethylbenzaldehyde (1) and 6-ethyl-2,4-dihydroxy-3,5-dimethylbenzaldehyde (2). generation of dtbaδr+te chimeric pkss by swapping the dtba r domain with the ausa (austinol biosynthesis) or anid_06448 te domain enabled the prod ... | 2013 | 23368695 |
| molecular genetic characterization of a cluster in a. terreus for biosynthesis of the meroterpenoid terretonin. | meroterpenoids are natural products produced from polyketide and terpenoid precursors. a gene targeting system for a. terreus nih2624 was developed, and a gene cluster for terretonin biosynthesis was characterized. the intermediates and shunt products were isolated from the mutant strains, and a pathway for terretonin biosynthesis is proposed. analysis of two meroterpenoid pathways corresponding to terretonin in a. terreus and austinol in a. nidulans reveals that they are closely related evoluti ... | 2012 | 23116177 |
| aspergillus oxylipin signaling and quorum sensing pathways depend on g protein-coupled receptors. | oxylipins regulate aspergillus development and mycotoxin production and are also involved in aspergillus quorum sensing mechanisms. despite extensive knowledge of how these oxylipins are synthesized and what processes they regulate, nothing is known about how these signals are detected and transmitted by the fungus. g protein-coupled receptors (gpcr) have been speculated to be involved as they are known oxylipin receptors in mammals, and many putative gpcrs have been identified in the aspergilli ... | 2012 | 23105976 |
| [application of pcr combined with reverse line blot assay in detection and identification of common pathogenic aspergillus in fungal sinusitis]. | to evaluate the feasibility of pcr/reverse line blot hybridization (rlb) assay in the detection and identification of clinical pathogens in fungal sinusitis (fs). | 2012 | 22455842 |
| xlnr-independent signaling pathway regulates both cellulase and xylanase genes in response to cellobiose in aspergillus aculeatus. | the expression levels of the cellulase and xylanase genes between the host strain and an xlnr disruptant were compared by quantitative rt-pcr (qpcr) to identify the genes controlled by xlnr-independent signaling pathway. the cellulose induction of the fi-carboxymethyl cellulase (cmc1) and fib-xylanase (xynib) genes was controlled by xlnr; in contrast, the cellulose induction of the fiii-avicelase (cbhi), fii-carboxymethyl cellulase (cmc2), and fia-xylanase (xynia) genes was controlled by an xlnr ... | 2012 | 22371227 |
| biodiversity of epilithic cyanobacteria from freshwater streams of kakoijana reserve forest, assam, india. | the biodiversity of epilithic cyanobacteria from one of the unexplored habitats of freshwater streams of kakoijana reserve forest of assam, india was estimated. this paper lists a total of 29 species representing 18 genera of 12 families and 4 orders as per recent system of classification. morphological descriptions, common habitats and distribution pattern were described for each species identified that were represented systematically. of these 29 species, 11 were unicellular, 9 non-heterocytou ... | 2007 | 23100670 |
| photodynamic effects of hypericin on photosynthetic electron transport and fluorescence of anacystis nidulans (synechococcus 6301). | we investigated the photodynamic action of hypericin, a natural naphthodianthrone, on photosynthetic electron transport and fluorescence of the cyanobacterium anacystis nidulans (synechococcus 6301). the most drastic effect was the inactivation of photosynthetic oxygen evolution in the presence of the electron acceptor phenyl-p-benzoquinone in aerobic cells which required 1 hypericin/5 chlorophyll a for half-maximal effect. anaerobic a. nidulans was only partially inactivated and variable chloro ... | 1996 | 24271302 |
| sources of fungal linamarases. | forty-four strains of aspergillus, penicillium, fusarium, trichoderma and rhizopus were grown on a liquid medium containing glucose and cassava-root extract. all of the aspergillus and fusarium strains, eight out of 10 penicillium strains and three of seven trichoderma strains showed linamarase activity. no such activity was detected in any rhizopus strain. the crude enzyme preparation from f. oxysporum had the highest affinity for linamarin whereas that from a. nidulans was the most heat-stable ... | 1995 | 24415020 |
| active-site histidines in recombinant cyanobacterial ribulose-1,5-bisphosphate carboxylase/oxygenase examined by site-directed mutagenesis. | the functions of his(291), his(295) and his(324) at the active-site of recombinant a. nidulans ribulose-1,5-bisphosphate carboxylase/ oxygenase have been explored by site-directed mutagenesis. replacement of his(291) by k or r resulted in unassembled proteins, while its replacement by e, q or n resulted in assembled but inactive proteins. these results are in accord with a metal ion-binding role of this residue in the activated ternary complex by analogy to x-ray crystallographic analyses of tob ... | 1994 | 24310117 |
| variation in the polypeptide composition of phycobilisomes from anacystis nidulans and three pigment mutants. | phycobilisomes, light harvesting antenna pigment systems, were studied from anacystis nidulans wild type and from several spontaneous pigment mutants selected for improved growth in far-red light (>650 nm). this is the first characterization and description of polypeptide composition of phycobilisomes from spontaneous mutants (not chemically induced) of a. nidulans. the mutants had significant changes in the phycobiliprotein content relative to chlorophyll (chl). two phycobiliproteins, c-phycocy ... | 1986 | 24443211 |
| temperature dependent changes in absorption and fluorescence properties of the cyanobacterium anacystis nidulans. | temperature dependent changes in absorbance and fluorescence of chlorophyll a (chl a) were analyzed in membrane fragments and in a chl-protein complex reconstituted with lipids isolated from the cyanobacterium anacystis nidulans. absorbance versus temperature curves measured at 656 nm showed an inflection point at 23-24°c and at 14-16°c in the membrane fragments prepared from a. nidulans cells, grown at 39° and 25°c, respectively. temperature-induced absorbance changes measured at 680 and 696 nm ... | 1984 | 24458777 |