scholarly journals Prediction of some peroxidase functions in Arabidopsis thaliana L. by bioinformatic search

2019 ◽  
Vol 23 (5) ◽  
pp. 615-623
Author(s):  
A. S. Tugbaeva ◽  
A. A. Ermoshin ◽  
I. S. Kiseleva

Peroxidases of class III are common in various organisms. They are involved in lignin biosynthesis and plant protection against stressors. Peroxidases are presented in many isoforms, whose role is not always clear. The aim of this study is to analyze the amino acid sequences of reference peroxidases with known functions and peroxidases from Arabidopsis thaliana L. whose functions are unknown and to consider their putative roles in lignin biosynthesis. The structural and functional organization of peroxidases was analyzed by bioinformatical methods applied to open Internet sources. Seven reference peroxidases were chosen from four plant species: Zinnia sp., Armoracia rusticana P.G. Gaertn., Lycopersicon esculentum L. и Populus alba L. Twenty-four amino acid sequences of homologous peroxidases from A. thaliana were selected for the analyses with the BLAST service. Their molecular weights and isoelectric points were calculated. Multiple alignments of amino acid sequences and phylogenetic analysis were done. Sites of binding to monolignol substrates were identified in seven peroxidases from A. thaliana, and the enzymes were assigned to the groups of Sor G-peroxidases. Amino acid replacements in the primary structures of peroxidases were analyzed. Peroxidases from A. thaliana were clustered with reference peroxidases. They formed six clusters on the phylogenetic tree, three of which contained only A. thaliana peroxidases. Peroxidases within each cluster had similar molecular weights and isoelectric points, common localization of expression, and similar functions. Thus, the use of bioinformatics, databases, and published data bring us to assumptions as to the functions of several A. thaliana class III peroxidases. AtPrx39 peroxidase was shown to be affine to sinapyl alcohol; AtPrx54, to p-coumaryl and coniferyl alcohols. They are likely to participate in lignin biosynthesis.

1978 ◽  
Vol 172 (3) ◽  
pp. 465-477 ◽  
Author(s):  
K G Hutson ◽  
L J Rogers ◽  
B G Haslett ◽  
D Boulter ◽  
R Cammack

Two ferredoxins were isolated from the cyanobacterium Nostoc strain MAC grown autotrophically in the light or heterotrophically in the dark. In either case approximately three times as much ferredoxin I as ferredoxin II was obtained. Both ferredoxins had absorption maxima at 276, 282 (shoulder), 330, 423 and 465 nm in the oxidized state, and each possessed a single 2 Fe-2S active centre. Their isoelectric points were approx. 3.2. The midpoint redox potentials of the ferredoxins differed markedly; that of ferredoxin I was −350mV and that of ferredoxin II was −445mV, at pH 8.0. The midpoint potential of ferredoxin II was unusual in being pH dependent. Ferredoxin I was most active in supporting NADP+ photoreduction by chloroplasts, whereas ferredoxin II was somewhat more active in pyruvate decarboxylation by the phosphoroclastic system of Clostridum pasteurianum. Though the molecular weights of the ferredoxins determined by ultracentrifugation were the same within experimetnal error, the amino acid compositions showed marked differences. The N-terminal amino acid sequences of ferredoxins I and II were determined by means of an automatic sequencer. There are 11–12 differences between the sequences of the first 32 residues. It appears that the two ferredoxins have evolved separately to fulfil different roles in the organism.


1968 ◽  
Vol 109 (1) ◽  
pp. 19-24 ◽  
Author(s):  
Louise Oliver ◽  
Anne Stockell Hartree

The cystine-containing peptides of horse growth hormone were isolated and their amino acid sequences determined. Four unique half-cystine residues occur in two peptides, one containing 11 and the other, at the C-terminus of the protein, 15 amino acids. These sequences are compared with published data on growth hormones from other species.


2006 ◽  
Vol 72 (5) ◽  
pp. 3321-3329 ◽  
Author(s):  
Kengo Inoue ◽  
Hiroshi Habe ◽  
Hisakazu Yamane ◽  
Hideaki Nojiri

ABSTRACT Nocardioides aromaticivorans IC177 is a gram-positive carbazole degrader. The genes encoding carbazole degradation (car genes) were cloned into a cosmid clone and sequenced partially to reveal 19 open reading frames. The car genes were clustered into the carAaCBaBbAcAd and carDFE gene clusters, encoding the enzymes responsible for the degradation of carbazole to anthranilate and 2-hydroxypenta-2,4-dienoate and of 2-hydroxypenta-2,4-dienoate to pyruvic acid and acetyl coenzyme A, respectively. The conserved amino acid motifs proposed to bind the Rieske-type [2Fe-2S] cluster and mononuclear iron, the Rieske-type [2Fe-2S] cluster, and flavin adenine dinucleotide were found in the deduced amino acid sequences of carAa, carAc, and carAd, respectively, which showed similarities with CarAa from Sphingomonas sp. strain KA1 (49% identity), CarAc from Pseudomonas resinovorans CA10 (31% identity), and AhdA4 from Sphingomonas sp. strain P2 (37% identity), respectively. Escherichia coli cells expressing CarAaAcAd exhibited major carbazole 1,9a-dioxygenase (CARDO) activity. These data showed that the IC177 CARDO is classified into class IIB, while gram-negative CARDOs are classified into class III or IIA, indicating that the respective CARDOs have diverse types of electron transfer components and high similarities of the terminal oxygenase. Reverse transcription-PCR (RT-PCR) experiments showed that the carAaCBaBbAcAd and carDFE gene clusters are operonic. The results of quantitative RT-PCR experiments indicated that transcription of both operons is induced by carbazole or its metabolite, whereas anthranilate is not an inducer. Biotransformation analysis showed that the IC177 CARDO exhibits significant activities for naphthalene, carbazole, and dibenzo-p-dioxin but less activity for dibenzofuran and biphenyl.


1998 ◽  
Vol 64 (2) ◽  
pp. 411-418 ◽  
Author(s):  
Katsuhisa Suzuki ◽  
Norio Wakao ◽  
Tetsuya Kimura ◽  
Kazuo Sakka ◽  
Kunio Ohmiya

ABSTRACT The arsenic resistance (ars) operon from plasmid pKW301 of Acidiphilium multivorum AIU 301 was cloned and sequenced. This DNA sequence contains five genes in the following order: arsR, arsD, arsA,arsB, arsC. The predicted amino acid sequences of all of the gene products are homologous to the amino acid sequences of the ars gene products of Escherichia coliplasmid R773 and IncN plasmid R46. The ars operon cloned from A. multivorum conferred resistance to arsenate and arsenite on E. coli. Expression of the arsgenes with the bacteriophage T7 RNA polymerase-promoter system allowedE. coli to overexpress ArsD, ArsA, and ArsC but not ArsR or ArsB. The apparent molecular weights of ArsD, ArsA, and ArsC were 13,000, 64,000, and 16,000, respectively. A primer extension analysis showed that the ars mRNA started at a position 19 nucleotides upstream from the arsR ATG in E. coli. Although the arsR gene of A. multivorum AIU 301 encodes a polypeptide of 84 amino acids that is smaller and less homologous than any of the other ArsR proteins, inactivation of the arsR gene resulted in constitutive expression of the ars genes, suggesting that ArsR of pKW301 controls the expression of this operon.


Genetics ◽  
1991 ◽  
Vol 127 (4) ◽  
pp. 801-809 ◽  
Author(s):  
A Konieczny ◽  
D F Voytas ◽  
M P Cummings ◽  
F M Ausubel

Abstract We describe a superfamily of Arabidopsis thaliana retrotransposable elements that consists of at least ten related families designated Ta1-Ta10. The Ta1 family has been described previously. Two genomic clones representing the Ta2 and Ta3 elements were isolated from an A. thaliana (race Landsberg erecta) lambda library using sequences derived from the reverse transcriptase region of Ta1 as hybridization probes. Nucleotide sequence analysis showed that the Ta1, Ta2 and Ta3 families share greater than 75% amino acid identity in pairwise comparisons of their reverse transcriptase and RNase H genes. In addition to Ta1, Ta2 and Ta3, we identified seven other related retrotransposon families in Landsberg erecta, Ta4-Ta10, using degenerate primers and the polymerase chain reaction to amplify a highly conserved region of retrotransposon-encoded reverse transcriptase. One to two copies of elements Ta2-Ta10 are present in the genomes of the A. thaliana races Landsberg erecta and Columbia indicating that the superfamily comprises at least 0.1% of the A. thaliana genome. The nucleotide sequences of the reverse transcriptase regions of the ten element families place them in the category of copia-like retrotransposons and phylogenetic analysis of the amino acid sequences suggests that horizontal transfer may have played a role in their evolution.


1983 ◽  
Vol 3 (4) ◽  
pp. 570-579
Author(s):  
G P Thill ◽  
R A Kramer ◽  
K J Turner ◽  
K A Bostian

The nucleotide sequence of 5'-noncoding and N-terminal coding regions of two coordinately regulated, repressible acid phosphatase genes from Saccharomyces cerevisiae were determined. These unlinked genes encode different, but structurally related polypeptides of molecular weights 60,000 and 56,000. The DNA sequences of their 5'-flanking regions show stretches of extensive homology upstream of, and surrounding, a "TATA" sequence and in a region in which heterogeneous 5' ends of the p60 mRNA were mapped. The predicted amino acid sequences encoded by the N-terminal regions of both genes were confirmed by determination of the amino acid sequence of the native exocellular acid phosphatase and the partial sequence of the presecretory polypeptide synthesized in a cell-free protein synthesizing system. The N-terminal region of the p60 polypeptide was shown to be characterized by a hydrophobic 17-amino acid signal polypeptide which is absent in the native exocellular protein and thought to be necessary for acid phosphatase secretion.


1976 ◽  
Vol 155 (1) ◽  
pp. 5-17 ◽  
Author(s):  
K B M Reid

1. Digestion of human subcomponent C1q with pepsin at pH4.45 for 20h at 37 degrees C fragmented most of the non-collagen-like amino acid sequences in the molecule to small peptides, whereas the entire regions of collagen-like sequence that comprised 38% by weight of the subcomponent C1q were left intact. 2. The collagen-like fraction of the digest was eluted in the void volume of a Sephadex G-200 column, was was showm to be composed of two major fragments when examined by electrophoresis on polyacrylamide gels run in buffers containing sodium dodecyl sulphate. These fragments were separated on CM-cellulose at pH4.9 in buffers containing 7.5M-urea. 3. Human subcomponent C1q on reduction and alkylation yields equimolar amounnts of three chains, which have been designated A, B and C [Reid et al. (1972) Biochem. J. 130, 749-763]. One of the pepsin fragments was shown to be composed of the N-terminal 95 residues of the A chain linked, via residue A4, by a single disulphide bond to a residue in the sequence B2-B6 in the N-terminal 91 residues of the B chain. The second pepsin fragment was shown to be composed of a disulphide-linked dimer of the N-terminal 94 residues of the C chain, the only disulphide bond being located at residue C4.4. The mol. wts. of the unoxidized and oxidized pepsin fragments were estimated from their amino acid compositions to be 20 000 and 18 200 for the A-B and C-C dimers and 11 400, 8800 and 9600 for the collagen-like fragments of the A, B and C chains respectively. Estimation of the molecular weights of the peptic fragments by polyacrylamide-gel electrophoresis run in the presence of sodium dodecyl sulphate gave values that were approx. 50% higher than expected from the amino acid sequence data. This is probably due to the high collagen-like sequence content of these fragments.


1986 ◽  
Vol 239 (1) ◽  
pp. 69-75 ◽  
Author(s):  
J Deistung ◽  
R N F Thorneley

Flavodoxin in the hydroquinone state acts as an electron donor to nitrogenase in several nitrogen-fixing organisms. The mid-point potentials for the oxidized-semiquinone and semiquinone-hydroquinone couples of flavodoxins isolated from facultative anaerobe Klebsiella pneumoniae (nifF-gene product, KpFld) and the obligate aerobe Azotobacter chroococcum (AcFld) were determined as a function of pH. The mid-point potentials of the semiquinone-hydroquinone couples of KpFld and AcFld are essentially independent of pH over the range pH 7-9, being -422 mV and -522 mV (normal hydrogen electrode) at pH 7.5 respectively. The mid-point potentials of the quinone-semiquinone couples at pH 7.5 are -200 mV (KpFld) and -133 mV (AcFld) with delta Em/pH of -65 +/- 4 mV (KpFld) and -55 +/- 2 mV (AcFld) over the range pH 7.0-9.5. This indicates that reduction of the quinone is coupled to protonation to yield a neutral semiquinone. The significance of these values with respect to electron transport to nitrogenase is discussed. The amino acid compositions, the N- and C-terminal amino acid sequences and the u.v.-visible spectra of KpFld and AcFld were determined and are compared with published data for flavodoxins isolated from Azotobacter vinelandii.


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