scholarly journals Alcohol oxidase expressed under nonmethylotrophic conditions is imported, assembled, and enzymatically active in peroxisomes of Hansenula polymorpha.

1988 ◽  
Vol 107 (5) ◽  
pp. 1669-1675 ◽  
Author(s):  
B Distel ◽  
I Van der Leÿ ◽  
M Veenhuis ◽  
H F Tabak
Keyword(s):  
Hansenula Polymorpha ◽  
Phosphoglycerate Kinase ◽  
Alcohol Oxidase ◽  
Growth Conditions ◽  
Extra Copy ◽  
Oxidase Gene ◽  
Endogenous Gene ◽  
Methylotrophic Growth ◽  
Crystalloid Inclusions ◽  
The One

We have introduced into Hansenula polymorpha an extra copy of its alcohol oxidase gene. This gene which is under the control of the Saccharomyces cerevisiae phosphoglycerate kinase promoter is integrated in a chromosome different from the one containing the endogenous gene. Cells with the extra alcohol oxidase gene, grown on glucose or ethanol as the sole carbon source, express enzymatically active alcohol oxidase. However, other enzymes characteristic for methylotrophic growth conditions are absent or present at low levels. Most of the alcohol oxidase occurs in the octameric state and immuno- and cytochemical evidence shows that it is located in a single enlarged peroxisome per cell. Such peroxisomes show crystalloid inclusions which are lacking in the peroxisomes present in glucose grown control cells. Our results suggest that import into peroxisomes of H. polymorpha, assembly and activation of alcohol oxidase is not conditionally dependent on adaptation to methylotrophic growth conditions and that proliferation of peroxisomes is a well-programmed process that is not triggered solely by overproduction of a peroxisomal protein.

Cloning and sequencing of the peroxisomal amine oxidase gene from Hansenula polymorpha

1989 ◽  
Vol 1008 (2) ◽  
pp. 157-167 ◽  
Author(s):  
Paul G Bruinenberg ◽  
Melchior Evers ◽  
Hans R Waterham ◽  
Jeroen Kuipers ◽  
Annika C Arnberg ◽  
...  
Keyword(s):  
Amine Oxidase ◽  
Hansenula Polymorpha ◽  
Cloning And Sequencing ◽  
Oxidase Gene

scholarly journals Pyruvate Carboxylase Is an Essential Protein in the Assembly of Yeast Peroxisomal Oligomeric Alcohol Oxidase

2003 ◽  
Vol 14 (2) ◽  
pp. 786-797 ◽  
Author(s):  
Paulina Ozimek ◽  
Ralf van Dijk ◽  
Kantcho Latchev ◽  
Carlos Gancedo ◽  
Dong Yuan Wang ◽  
...  
Keyword(s):  
Pyruvate Carboxylase ◽  
Tricarboxylic Acid Cycle ◽  
Hansenula Polymorpha ◽  
Alcohol Oxidase ◽  
Methylotrophic Yeast ◽  
Tricarboxylic Acid ◽  
Matrix Proteins ◽  
Growth Media ◽  
Fad Binding

Hansenula polymorpha ass3 mutants are characterized by the accumulation of inactive alcohol oxidase (AO) monomers in the cytosol, whereas other peroxisomal matrix proteins are normally activated and sorted to peroxisomes. These mutants also have a glutamate or aspartate requirement on minimal media. Cloning of the corresponding gene resulted in the isolation of the H. polymorpha PYC gene that encodes pyruvate carboxylase (HpPyc1p). HpPyc1p is a cytosolic, anapleurotic enzyme that replenishes the tricarboxylic acid cycle with oxaloacetate. The absence of this enzyme can be compensated by addition of aspartate or glutamate to the growth media. We show that HpPyc1p protein but not the enzyme activity is essential for import and assembly of AO. Similar results were obtained in the related yeast Pichia pastoris. In vitro studies revealed that HpPyc1p has affinity for FAD and is capable to physically interact with AO protein. These data suggest that in methylotrophic yeast pyruvate carboxylase plays a dual role in that, besides its well-characterized metabolic function as anapleurotic enzyme, the protein fulfils a specific role in the AO sorting and assembly process, possibly by mediating FAD-binding to AO monomers.

scholarly journals Fourier multipliers on spaces of distributions

1986 ◽  
Vol 29 (3) ◽  
pp. 309-327 ◽  
Author(s):  
W. Lamb
Keyword(s):  
Banach Spaces ◽  
Growth Conditions ◽  
Fourier Multipliers ◽  
Bounded Operators ◽  
Vertical Strip ◽  
One Dimensional ◽  
The One ◽  
Image Position ◽  
Complex Valued

In [8], Rooney defines a class of complex-valued functions ζ each of which is analytic in a vertical strip α(ζ)< Res < β(ζ) in the complex s-plane and satisfies certain growth conditions as |Im s| →∞ along fixed lines Re s = c lying within this strip. These conditions mean that the functionsfulfil the requirements of the one-dimensional Mihlin-Hörmander theorem (see [6, p. 417]) and so can be regarded as Fourier multipliers for the Banach spaces . Consequently, each function gives rise to a family of bounded operators W[ζ,σ] σ ∈(α(ζ),β(ζ)), on , 1<p<∞.

Regulation of conductive Cl- transport in human fibroblasts

1988 ◽  
Vol 255 (4) ◽  
pp. C552-C558 ◽  
Author(s):  
P. Lin ◽  
M. Ahluwalia ◽  
E. Gruenstein
Keyword(s):  
Human Fibroblasts ◽  
Normal Growth ◽  
Growth Conditions ◽  
Disulfonic Acid ◽  
Ionophore A23187 ◽  
Simultaneous Exposure ◽  
Electrically Conductive ◽  
Cl Channels ◽  
The One ◽  
Cl Conductance

Under normal growth conditions, approximately 20% of the efflux of Cl- from human fibroblasts occurs via an electrically conductive pathway or Cl- channel. This basal Cl- conductance is insensitive to the Cl- -anion exchange inhibitor 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS) and to the Cl- -cation cotransport inhibitor bumetanide. Exposure of the cells to dibutyryl adenosine 3',5'-cyclic monophosphate (cAMP) for 15 min increases the electrically conductive component of Cl- efflux by approximately 20%. Unlike the basal Cl- conductance, the cAMP-activated channel is DIDS sensitive, indicating that cAMP activates a different Cl- pathway from the one responsible for the basal Cl- conductance. Elevation of intracellular Ca2+ by addition of the ionophore A23187 also stimulates Cl- efflux via a DIDS inhibitable, electrically conductive Cl- pathway. That the cAMP- and Ca2+-stimulated pathways are different is suggested by the observation that simultaneous exposure of cells to optimal levels of dibutyryl cAMP and A23187 results in an increased Cl- efflux equal to the sum of the two factors acting independently. Prostaglandin E1, a known activator of adenylate cyclase, also elevates the levels of intracellular free Ca2+ in these cells and concomitantly activates both the cAMP- and the Ca2+-stimulated Cl- channels. Although regulated, Cl- channels are known to function in the modulation of nerve and muscle excitability, their role in fibroblast function is not clear.

scholarly journals Variation and Relationships among Agronomic Traits in Durum Wheat [Triticum turgidum(L.) Thell. ssp.turgidumconv.durum(Desf.) MacKey] under South Mediterranean Growth Conditions: Stepwise and Path Analyses

2018 ◽  
Vol 2018 ◽  
pp. 1-11 ◽  
Author(s):  
Ali Mansouri ◽  
Bachir Oudjehih ◽  
Abdelkader Benbelkacem ◽  
Zine El Abidine Fellahi ◽  
Hamenna Bouzerzour
Keyword(s):  
Grain Yield ◽  
Durum Wheat ◽  
Harvest Index ◽  
Agronomic Traits ◽  
Triticum Turgidum ◽  
Canopy Temperature ◽  
Growth Conditions ◽  
Path Analyses ◽  
Spike Number ◽  
The One

Relationships among agronomic traits and grain yield were investigated in 56 genotypes of durum wheat (Triticum durumDesf.). The results indicated the presence of sufficient variability nearly for all measured traits. Heritability and expected genetic gain varied among traits. Aboveground biomass, harvest index, and spike number were the most grain yield-influencing traits. Early genotypes showed above-average grain and biological yields, spike number, and lower canopy temperature. Assessed genotypes were clustered into three groups which differed mainly for biological, economical, straw, and grain yields, on the one hand, and plant height, chlorophyll content, and canopy temperature, on the other hand. Selection for direct use from clusters carrying best combinations of yield-related traits and crosses to be made between genotypes belonging to contrasted clusters were suggested to generate more variability. Selection preferentially for spike number, biological yield, harvest index, and canopy temperature to accumulate favorable alleles in the selected entries for future uses is suggested.

scholarly journals The differentiation ofStreptococcus cremorisandStreptococcus lactisby means of bacteriophage action

1946 ◽  
Vol 44 (4) ◽  
pp. 264-270 ◽  
Author(s):  
G. J. E. Hunter
Keyword(s):  
Growth Conditions ◽  
The Other ◽  
Sensitivity Tests ◽  
Phage Sensitivity ◽  
Temperature And Growth ◽  
The One ◽  
Almost All ◽  
Group D

1. A series of lactic streptococci which were almost all capable of clotting milk in 24 hr. at 22°C. were divided into two groups on the basis of a few simple biochemical and morphological tests. The two groups corresponded to what some workers consider to be the speciesStr.lactisandStr.cremoris.2. A series of phage races were tested for their action on the streptococci under various temperature and growth conditions.3. The characteristics of phage attack on the organisms tended to confirm the division intoStr.lactisandStr.cremorisspecies. Each of the strains of the long-chainedcremoristype was attacked by only a few phages at the most, sometimes by a single phage only, whereas each of thelactis(short-chained) strains was attacked by a variety of phages. Furthermore, with two exceptions, the phage attacking thecremoristypes on the one hand and thelactistypes on the other formed quite separate and distinct groups.4. None of the phages acted upon the several available strains ofStr.faecalisand other group D (Lancefield) streptococci.5. The evidence obtained from the phage sensitivity tests seems to justify the division of the lactic streptococci into two species,Str. lactisandStr. cremoris.The author is indebted to Dr H. R. Whitehead for his interest in this work, and for helpful criticism and advice.

scholarly journals Characterization of Conserved Tandem Donor Sites and Intronic Motifs Required for Alternative Splicing in Corticosteroid Receptor Genes

Endocrinology ◽  
2009 ◽  
Vol 150 (11) ◽  
pp. 4958-4967 ◽  
Author(s):  
Caroline Rivers ◽  
Andrea Flynn ◽  
Xiaoxiao Qian ◽  
Laura Matthews ◽  
Stafford Lightman ◽  
...  
Keyword(s):  
Alternative Splicing ◽  
Splice Site ◽  
Rna Binding ◽  
Rna Binding Proteins ◽  
Splice Variants ◽  
Mammalian Species ◽  
Donor Site ◽  
Small Nuclear Rna ◽  
Endogenous Gene ◽  
The One

Alternative splicing events from tandem donor sites result in mRNA variants coding for additional amino acids in the DNA binding domain of both the glucocorticoid (GR) and mineralocorticoid (MR) receptors. We now show that expression of both splice variants is extensively conserved in mammalian species, providing strong evidence for their functional significance. An exception to the conservation of the MR tandem splice site (an A at position +5 of the MR+12 donor site in the mouse) was predicted to decrease U1 small nuclear RNA binding. In accord with this prediction, we were unable to detect the MR+12 variant in this species. The one exception to the conservation of the GR tandem splice site, an A at position +3 of the platypus GRγ donor site that was predicted to enhance binding of U1 snRNA, was unexpectedly associated with decreased expression of the variant from the endogenous gene as well as a minigene. An intronic pyrimidine motif present in both GR and MR genes was found to be critical for usage of the downstream donor site, and overexpression of TIA1/TIAL1 RNA binding proteins, which are known to bind such motifs, led to a marked increase in the proportion of GRγ and MR+12. These results provide striking evidence for conservation of a complex splicing mechanism that involves processes other than stochastic spliceosome binding and identify a mechanism that would allow regulation of variant expression.

scholarly journals Flavin adenine dinucleotide binding is the crucial step in alcohol oxidase assembly in the yeast Hansenula polymorpha

Yeast ◽  
1996 ◽  
Vol 12 (10) ◽  
pp. 917-923 ◽  
Author(s):  
Melchior E. Evers ◽  
Vladimir Titorenko ◽  
Wim Harder ◽  
Ida van der Klei ◽  
Marten Veenhuis
Keyword(s):  
Flavin Adenine Dinucleotide ◽  
Hansenula Polymorpha ◽  
Alcohol Oxidase ◽  
Crucial Step

scholarly journals Routing of Hansenula polymorpha Alcohol Oxidase: An Alternative Peroxisomal Protein-sorting Machinery

2004 ◽  
Vol 15 (3) ◽  
pp. 1347-1355 ◽  
Author(s):  
Katja Gunkel ◽  
Ralf van Dijk ◽  
Marten Veenhuis ◽  
Ida J. van der Klei
Keyword(s):  
Amino Acids ◽  
Protein Translocation ◽  
Hansenula Polymorpha ◽  
Alcohol Oxidase ◽  
N Terminus ◽  
Dependent Protein ◽  
Peptides Synthesis ◽  
Translocation Pathway ◽  
Tpr Domain ◽  
Fad Binding

Import of Hansenula polymorpha alcohol oxidase (AO) into peroxisomes is dependent on the PTS1 receptor, HpPex5p. The PTS1 of AO (-LARF) is sufficient to direct reporter proteins to peroxisomes. To study AO sorting in more detail, strains producing mutant AO proteins were constructed. AO containing a mutation in the FAD binding fold was mislocalized to the cytosol. This indicates that the PTS1 of AO is not sufficient for import of AO. AO protein in which the PTS1 was destroyed (-LARA) was normally sorted to peroxisomes. Moreover, C-terminal deletions of up to 16 amino acids did not significantly affect AO import, indicating that the PTS1 was not necessary for targeting. Consistent with these observations we found that AO import occurred independent from the C-terminal TPR-domain of HpPex5p, known to bind PTS1 peptides. Synthesis of the N-terminal domain (amino acids 1-272) of HpPex5p in pex5 cells restored AO import, whereas other PTS1 proteins were mislocalized to the cytosol. These data indicate that AO is imported via a novel HpPex5p-dependent protein translocation pathway, which does not require the PTS1 of AO and the C-terminal TPR domains of HpPex5p, but involves FAD binding and the N-terminus of HpPex5p.

Sign in / Sign up

Export Citation Format

Share Document