Purification and Characterization of Cytochrome 553 from the Chrysophycean Alga Monochrysis lutheri

1971 ◽  
Vol 49 (6) ◽  
pp. 641-646 ◽  
Author(s):  
M. V. Laycock ◽  
J. S. Craigie

Cytochrome 553, an electron carrier in photosynthesis and a functional analogue of cytochrome f of higher plants, was isolated from Monochrysis lutheri and purified by salt fractionation, chromatography, and isoelectric focussing. Absorption maxima occurred at 275, 320, 416, 523, and 553 nm in the reduced form. The α-absorption peak was symmetrical and had an extinction coefficient of 25.9 mM−1 cm−1. The molecular weight was 11 100 by equilibrium centrifugation, 12 400 from iron determinations, and 10 300 from the amino acid composition. The molecule consisted of one heme group and 91 amino acid residues including two cysteine residues and one each of histidine, arginine, tryptophan, methionine, and proline. Other physical properties measured were: the sedimentation coefficient, 1.3 S; the normal oxidation reduction potential, + 0.388 V; and the isoelectric point, pH 3.75.

BMC Genomics ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Zhongying Wang ◽  
Qixuan Wang ◽  
Hao Wu ◽  
Zhiwu Huang

Abstract Background Prestin (SLC26A5) is responsible for acute sensitivity and frequency selectivity in the vertebrate auditory system. Limited knowledge of prestin is from experiments using site-directed mutagenesis or domain-swapping techniques after the amino acid residues were identified by comparing the sequence of prestin to those of its paralogs and orthologs. Frog prestin is the only representative in amphibian lineage and the studies of it were quite rare with only one species identified. Results Here we report a new coding sequence of SLC26A5 for a frog species, Rana catesbeiana (the American bullfrog). In our study, the SLC26A5 gene of Rana has been mapped, sequenced and cloned successively using RNA-Seq. We measured the nonlinear capacitance (NLC) of prestin both in the hair cells of Rana’s inner ear and HEK293T cells transfected with this new coding gene. HEK293T cells expressing Rana prestin showed electrophysiological features similar to that of hair cells from its inner ear. Comparative studies of zebrafish, chick, Rana and an ancient frog species showed that chick and zebrafish prestin lacked NLC. Ancient frog’s prestin was functionally different from Rana. Conclusions We mapped and sequenced the SLC26A5 of the Rana catesbeiana from its inner ear cDNA using RNA-Seq. The Rana SLC26A5 cDNA was 2292 bp long, encoding a polypeptide of 763 amino acid residues, with 40% identity to mammals. This new coding gene could encode a functionally active protein conferring NLC to both frog HCs and the mammalian cell line. While comparing to its orthologs, the amphibian prestin has been evolutionarily changing its function and becomes more advanced than avian and teleost prestin.


2004 ◽  
Vol 186 (15) ◽  
pp. 4885-4893 ◽  
Author(s):  
Takane Katayama ◽  
Akiko Sakuma ◽  
Takatoshi Kimura ◽  
Yutaka Makimura ◽  
Jun Hiratake ◽  
...  

ABSTRACT A genomic library of Bifidobacterium bifidum constructed in Escherichia coli was screened for the ability to hydrolyze the α-(1→2) linkage of 2′-fucosyllactose, and a gene encoding 1,2-α-l-fucosidase (AfcA) was isolated. The afcA gene was found to comprise 1,959 amino acid residues with a predicted molecular mass of 205 kDa and containing a signal peptide and a membrane anchor at the N and C termini, respectively. A domain responsible for fucosidase activity (the Fuc domain; amino acid residues 577 to 1474) was localized by deletion analysis and then purified as a hexahistidine-tagged protein. The recombinant Fuc domain specifically hydrolyzed the terminal α-(1→2)-fucosidic linkages of various oligosaccharides and a sugar chain of a glycoprotein. The stereochemical course of the hydrolysis of 2′-fucosyllactose was determined to be inversion by using 1H nuclear magnetic resonance. The primary structure of the Fuc domain exhibited no similarity to those of any glycoside hydrolases (GHs) but showed high similarity to those of several hypothetical proteins in a database. Thus, it was revealed that the AfcA protein constitutes a novel inverting GH family (GH family 95).


2021 ◽  
Vol 42 (1) ◽  
pp. 14-23
Author(s):  
B.B. Patnaik ◽  
◽  
S. Baliarsingh ◽  
S. Sahoo ◽  
J.M. Chung ◽  
...  

Aim: Identification of full-length ORF of hemocyanin subunit-1 (Mr_HC_1) from the hepatopancreas transcriptome of freshwater prawn, Macrobrachium rosenbergii infected with Vibrio harveyi and characterization of its sequence and structure by in silico tools and softwares. Methodology: Illumina HiSeq and de novo assembled unigenes were scanned against PANM-DB to screen Mr_HC_1. FGENESH gene prediction and SMART programs were used to predict the ORF region. Subsequently, Clustal X2 and MEGA in-silico tools were used to understand the sequence relatedness and evolutionary status of Mr_HC_1. Structural prediction was performed by SWISS-MODEL and Ramachandran plot modeling programs Results: The full-length ORF was 1983 bp in length encoding a polypeptide of 661 amino acid residues. Mr_HC_1 showed a putative signal peptide of 21 amino acid residues at the N-terminus and three hemocyanin domains. Homology analysis of Mr_HC_1 amino acid sequence confirms maximum identity to M. nipponense hemocyanin subunit-1 (Mn_HC_1). Phylogenetic analysis showed that Mr_HC_1 is more closely related to the hemocyanin γ-type subunit of freshwater shrimps. Homology modeling of Mr_HC_1 showed homo-hexameric protein containing 12 copper ions. With a QMEAN score of -3.33 and model-template sequence identity of 59.15%, the predicted model of Mr_HC_1 is convincing Interpretation: This study characterizes the hemocyanin γ-type subunit protein of freshwater prawn, M. rosenbergii for future studies on host defense mechanisms.


Biochemistry ◽  
2010 ◽  
Vol 49 (41) ◽  
pp. 8922-8928 ◽  
Author(s):  
Damon Huber ◽  
Alain Chaffotte ◽  
Markus Eser ◽  
Anne-Gaëlle Planson ◽  
Jon Beckwith

2015 ◽  
Vol 39 (5) ◽  
pp. 3319-3326 ◽  
Author(s):  
Madhusudana M. B. Reddy ◽  
K. Basuroy ◽  
S. Chandrappa ◽  
B. Dinesh ◽  
B. Vasantha ◽  
...  

γn amino acid residues can be incorporated into structures in γn and hybrid sequences containing folded and extended α and δ residues.


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