DNA sequence similarity, cell wall mannans and physiological characteristics in some strains of Candida utilis, Hansenula jadinii and Hansenula petersonii

1979 ◽  
Vol 45 (3) ◽  
pp. 451-463 ◽  
Author(s):  
P. L. Manachini
2005 ◽  
Vol 391 (2) ◽  
pp. 409-415 ◽  
Author(s):  
Anna Kärkönen ◽  
Alain Murigneux ◽  
Jean-Pierre Martinant ◽  
Elodie Pepey ◽  
Christophe Tatout ◽  
...  

UDPGDH (UDP-D-glucose dehydrogenase) oxidizes UDP-Glc (UDP-D-glucose) to UDP-GlcA (UDP-D-glucuronate), the precursor of UDP-D-xylose and UDP-L-arabinose, major cell wall polysaccharide precursors. Maize (Zea mays L.) has at least two putative UDPGDH genes (A and B), according to sequence similarity to a soya bean UDPGDH gene. The predicted maize amino acid sequences have 95% similarity to that of soya bean. Maize mutants with a Mu-element insertion in UDPGDH-A or UDPGDH-B were isolated (udpgdh-A1 and udpgdh-B1 respectively) and studied for changes in wall polysaccharide biosynthesis. The udpgdh-A1 and udpgdh-B1 homozygotes showed no visible phenotype but exhibited 90 and 60–70% less UDPGDH activity respectively than wild-types in a radiochemical assay with 30 μM UDP-glucose. Ethanol dehydrogenase (ADH) activity varied independently of UDPGDH activity, supporting the hypothesis that ADH and UDPGDH activities are due to different enzymes in maize. When extracts from wild-types and udpgdh-A1 homozygotes were assayed with increasing concentrations of UDP-Glc, at least two isoforms of UDPGDH were detected, having Km values of approx. 380 and 950 μM for UDP-Glc. Leaf and stem non-cellulosic polysaccharides had lower Ara/Gal and Xyl/Gal ratios in udpgdh-A1 homozygotes than in wild-types, whereas udpgdh-B1 homozygotes exhibited more variability among individual plants, suggesting that UDPGDH-A activity has a more important role than UDPGDH-B in UDP-GlcA synthesis. The fact that mutation of a UDPGDH gene interferes with polysaccharide synthesis suggests a greater importance for the sugar nucleotide oxidation pathway than for the myo-inositol pathway in UDP-GlcA biosynthesis during post-germinative growth of maize.


1963 ◽  
Vol 9 (1) ◽  
pp. 117-127
Author(s):  
E. R. Blakley

The rate of fermentation of glucose by suspensions of Candida utilis at acid pH values is reduced by alkyl benzene sulphonate in the range 75 to 250 γ/ml. Concentrations of alkyl benzene sulphonate below 75 γ/ml decrease the rate of fermentation of glucose above pH 7 and respiration at all pH values. An upper limit of 70 to 90% inhibition of fermentation or respiration is obtained at concentrations of alkyl benzene sulphonate above 250 γ/ml, except at pH 4.2 where complete inhibition is obtained. The effect of alkyl benzene sulphonate on the fermentation of glucose by yeast protoplasts is similar to the effect observed for intact yeasts. Some enzymatic reactions of cell-free extracts are inhibited by concentrations of alkyl benzene sulphonate lower than that required to affect fermentation by intact cells. The enzyme components of the cell-free preparation appear to vary in their sensitivity to the surfactant. The results support the view that the surfactant in the micellar form disrupts the cell wall of the yeast, and unassociated molecules inactivate some enzymes vital for the metabolism of the cell.


2020 ◽  
Vol 401 (12) ◽  
pp. 1389-1405
Author(s):  
Lars-Oliver Essen ◽  
Marian Samuel Vogt ◽  
Hans-Ulrich Mösch

AbstractSelective adhesion of fungal cells to one another and to foreign surfaces is fundamental for the development of multicellular growth forms and the successful colonization of substrates and host organisms. Accordingly, fungi possess diverse cell wall-associated adhesins, mostly large glycoproteins, which present N-terminal adhesion domains at the cell surface for ligand recognition and binding. In order to function as robust adhesins, these glycoproteins must be covalently linkedto the cell wall via C-terminal glycosylphosphatidylinositol (GPI) anchors by transglycosylation. In this review, we summarize the current knowledge on the structural and functional diversity of so far characterized protein families of adhesion domains and set it into a broad context by an in-depth bioinformatics analysis using sequence similarity networks. In addition, we discuss possible mechanisms for the membrane-to-cell wall transfer of fungal adhesins by membrane-anchored Dfg5 transglycosidases.


1993 ◽  
Vol 13 (10) ◽  
pp. 6012-6023 ◽  
Author(s):  
R Cafferkey ◽  
P R Young ◽  
M M McLaughlin ◽  
D J Bergsma ◽  
Y Koltin ◽  
...  

Rapamycin is a macrolide antifungal agent that exhibits potent immunosuppressive properties. In Saccharomyces cerevisiae, rapamycin sensitivity is mediated by a specific cytoplasmic receptor which is a homolog of human FKBP12 (hFKBP12). Deletion of the gene for yeast FKBP12 (RBP1) results in recessive drug resistance, and expression of hFKBP12 restores rapamycin sensitivity. These data support the idea that FKBP12 and rapamycin form a toxic complex that corrupts the function of other cellular proteins. To identify such proteins, we isolated dominant rapamycin-resistant mutants both in wild-type haploid and diploid cells and in haploid rbp1::URA3 cells engineered to express hFKBP12. Genetic analysis indicated that the dominant mutations are nonallelic to mutations in RBP1 and define two genes, designated DRR1 and DRR2 (for dominant rapamycin resistance). Mutant copies of DRR1 and DRR2 were cloned from genomic YCp50 libraries by their ability to confer drug resistance in wild-type cells. DNA sequence analysis of a mutant drr1 allele revealed a long open reading frame predicting a novel 2470-amino-acid protein with several motifs suggesting an involvement in intracellular signal transduction, including a leucine zipper near the N terminus, two putative DNA-binding sequences, and a domain that exhibits significant sequence similarity to the 110-kDa catalytic subunit of both yeast (VPS34) and bovine phosphatidylinositol 3-kinases. Genomic disruption of DRR1 in a mutant haploid strain restored drug sensitivity and demonstrated that the gene encodes a nonessential function. DNA sequence comparison of seven independent drr1dom alleles identified single base pair substitutions in the same codon within the phosphatidylinositol 3-kinase domain, resulting in a change of Ser-1972 to Arg or Asn. We conclude either that DRR1 (alone or in combination with DRR2) acts as a target of FKBP12-rapamycin complexes or that a missense mutation in DRR1 allows it to compensate for the function of the normal drug target.


2021 ◽  
Author(s):  
Maja Brus-Szkalej ◽  
Christian B. Andersen ◽  
Ramesh R. Vetukuri ◽  
Laura J. Grenville-Briggs Didymus

Transglutaminases (TGases) are enzymes highly conserved among prokaryotic and eukaryotic organisms, where their role is to catalyse protein cross-linking. One of the putative TGases of Phytophthora infestans has previously been shown to be localised to the cell wall. Based on sequence similarity we were able to identify six more genes annotated as putative TGases and show that these seven genes group together in phylogenetic analysis. All of the seven proteins are predicted to contain transmembrane helices and both a TGase domain and a MANSC domain, the latter of which was previously shown to play a role in protein stability. Chemical inhibition of transglutaminase activity and silencing of the entire family of the putative cell wall TGases are both lethal to P. infestans indicating the importance of these proteins in cell wall formation and stability. The intermediate phenotype obtained with lower drug concentrations and less efficient silencing displays a number of deformations to germ tubes and appressoria. Both chemically treated and silenced lines show lower pathogenicity than the wild type in leaf infection assays. Finally, we show that appressoria of P. infestans possess the ability to build up turgor pressure and that this ability is decreased by chemical inhibition of TGases.


1988 ◽  
Vol 8 (2) ◽  
pp. 843-853
Author(s):  
M J Henkemeyer ◽  
R L Bennett ◽  
F B Gertler ◽  
F M Hoffmann

We report our molecular characterization of the Drosophila melanogaster Abelson gene (abl), a gene in which recessive loss-of-function mutations result in lethality at the pupal stage of development. This essential gene consists of 10 exons extending over 26 kilobase pairs of genomic DNA. The DNA sequence encodes a protein of 1,520 amino acids with strong sequence similarity to the human c-abl proto-oncogene beginning in the type lb 5' exon and extending through the region essential for tyrosine kinase activity. When the tyrosine kinase homologous region was expressed in Escherichia coli, phosphorylation of proteins on tyrosine residues was observed with an antiphosphotyrosine antibody. These results show that the abl gene is highly conserved through evolution and encodes a functional tyrosine protein kinase required for Drosophila development.


Author(s):  
Dan Wei ◽  
Qingshan Jiang ◽  
Sheng Li

Similarity analysis of DNA sequences is a fundamental research area in Bioinformatics. The characteristic distribution of L-tuple, which is the tuple of length L, reflects the valuable information contained in a biological sequence and thus may be used in DNA sequence similarity analysis. However, similarity analysis based on characteristic distribution of L-tuple is not effective for the comparison of highly conservative sequences. In this paper, a new similarity measurement approach based on Triplets of Nucleic Acid Bases (TNAB) is introduced for DNA sequence similarity analysis. The new approach characterizes both the content feature and position feature of a DNA sequence using the frequency and position of occurrence of TNAB in the sequence. The experimental results show that the approach based on TNAB is effective for analysing DNA sequence similarity.


2004 ◽  
Vol 54 (3) ◽  
pp. 783-789 ◽  
Author(s):  
Célia M. Manaia ◽  
Balbina Nogales ◽  
Norbert Weiss ◽  
Olga C. Nunes

A Gram-positive, molinate-degrading bacterium, strain ON4T (=DSM 13485T=LMG 21909T), was isolated from a mixed bacterial culture able to mineralize the herbicide molinate. The strain was strictly aerobic, oxidase- and catalase-positive and non-acid-fast, with a growth temperature of 10–41 °C. It contained the major menaquinone MK-9 and a cell-wall peptidoglycan based on d-ornithine. 16S rDNA sequence analysis revealed that the strain formed a distinct line of descent in the family Microbacteriaceae, showing the highest 16S rDNA similarity (∼95 %) to members of the genus Curtobacterium and ‘Brevibacterium helvolum’ DSM 20419 (=ATCC 13715). The latter was reported to have the cell-wall peptidoglycan type B2γ and the major menaquinone MK-9, which are typical of Clavibacter, but it is clearly separated from this genus at the phylogenetic level. Based on low values of 16S rDNA sequence similarity to previously described genera and their distinctive phenotypic characteristics, it is proposed that strains ON4T and ‘B. helvolum’ DSM 20419 be classified as two novel genera and species, with the respective names Gulosibacter molinativorax gen. nov., sp. nov. and Pseudoclavibater helvolus gen. nov., sp. nov.


1976 ◽  
Vol 54 (11) ◽  
pp. 927-934 ◽  
Author(s):  
T. G. Villa ◽  
V. Notario ◽  
T. Benítez ◽  
J. R. Villanueva

An exo-1,3-β-glucanase (EC 3.2.1.—) has been purified from the culture fluid of the yeast Candida utilis, and its biochemical properties have been studied. The amino acid analysis revealed a high content of acidic amino acids. The purified enzyme had 20% carbohydrate and a net negative charge showing higher affinity for laminarin than for p-nitrophenyl-β-D-glucopyranoside and yeast cell-wall 1,3-β-glucans. In addition, the enzyme hydrolyzed the substrates starting from the nonreducing ends, releasing glucose as the exclusive hydrolysis product. The enzyme activity was strongly inhibited by lactones and also by some heavy-metal ions.


2013 ◽  
Vol 63 (Pt_1) ◽  
pp. 241-248 ◽  
Author(s):  
Learn-Han Lee ◽  
Yoke-Kqueen Cheah ◽  
Shiran Mohd Sidik ◽  
Qing-Yi Xie ◽  
Yi-Li Tang ◽  
...  

Three novel actinobacteria, strains 39T, 40 and 41, were isolated from soil collected from Barrientos Island in the Antarctic. The taxonomic status of these strains was determined using a polyphasic approach. Comparison of 16S rRNA gene sequences revealed that strain 39T represented a novel lineage within the family Dermacoccaceae and was most closely related to members of the genera Demetria (96.9 % 16S rRNA gene sequence similarity), Branchiibius (95.7 %), Dermacoccus (94.4–95.3 %), Calidifontibacter (94.6 %), Luteipulveratus (94.3 %), Yimella (94.2 %) and Kytococcus (93.1 %). Cells were irregular cocci and short rods. The peptidoglycan type was A4α with an l-Lys–l-Ser–d-Asp interpeptide bridge. The cell-wall sugars were galactose and glucose. The major menaquinone was MK-8(H4). The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, phosphoglycolipid, two glycolipids and one unknown phospholipid. The acyl type of the cell-wall polysaccharide was N-acetyl. The major cellular fatty acids were anteiso-C17 : 0 (41.97 %), anteiso-C17 : 1ω9c (32.16 %) and iso-C16 : 0 (7.68 %). The DNA G+C content of strain 39T was 68.4 mol%. On the basis of phylogenetic and phenotypic differences from other genera of the family Dermacoccaceae , a novel genus and species, Barrientosiimonas humi gen. nov., sp. nov., is proposed; the type strain of the type species is 39T ( = CGMCC 4.6864T  = DSM 24617T).


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