Crystal structure of hemoglobin from mouse (Mus musculus) compared with those from other small animals and humans

Mice (Mus musculus) are nocturnal small animals belonging to the rodent family that live in burrows, an environment in which significantly high CO2 levels prevail. It is expected that mouse hemoglobin (Hb) plays an important role in their adaptation to living in such a high-CO2 environment, while many other species cannot. In the present study, mouse Hb was purified and crystallized at a physiological pH of 7 in the orthorhombic space group P212121; the crystals diffracted to 2.8 Å resolution. The primary amino-acid sequence and crystal structure of mouse Hb were compared with those of mammalian Hbs in order to investigate the structure–function relationship of mouse Hb. Differences were observed from guinea pig Hb in terms of amino-acid sequence and from cat Hb in overall structure (in terms of r.m.s.d.). The difference in r.m.s.d. from cat Hb may be due to the existence of the molecule in a conformation other than the R-state. Analysis of tertiary- and quaternary-structural features, the α1β2 interface region and the heme environment without any ligands in all four heme groups showed that mouse methemoglobin is in an intermediate state between the R-state and the T-state that is much closer to the R-state conformation.

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Data mining of coronavirus: SARS-CoV-2, SARS-CoV and MERS-CoV

BMC Research Notes ◽

10.1186/s13104-021-05561-4 ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Jung Eun Huh ◽

Seunghee Han ◽

Taeseon Yoon

Keyword(s):

Machine Learning ◽

Amino Acid ◽

Amino Acid Sequence ◽

Decision Tree ◽

Machine Learning Algorithms ◽

High Similarity ◽

Incubation Periods ◽

Initial Question ◽

The Difference ◽

Blast Program

Abstract Objective In this study we compare the amino acid and codon sequence of SARS-CoV-2, SARS-CoV and MERS-CoV using different statistics programs to understand their characteristics. Specifically, we are interested in how differences in the amino acid and codon sequence can lead to different incubation periods and outbreak periods. Our initial question was to compare SARS-CoV-2 to different viruses in the coronavirus family using BLAST program of NCBI and machine learning algorithms. Results The result of experiments using BLAST, Apriori and Decision Tree has shown that SARS-CoV-2 had high similarity with SARS-CoV while having comparably low similarity with MERS-CoV. We decided to compare the codons of SARS-CoV-2 and MERS-CoV to see the difference. Though the viruses are very alike according to BLAST and Apriori experiments, SVM proved that they can be effectively classified using non-linear kernels. Decision Tree experiment proved several remarkable properties of SARS-CoV-2 amino acid sequence that cannot be found in MERS-CoV amino acid sequence. The consequential purpose of this paper is to minimize the damage on humanity from SARS-CoV-2. Hence, further studies can be focused on the comparison of SARS-CoV-2 virus with other viruses that also can be transmitted during latent periods.

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Intracellular Retention of the Corticotrophin-releasing Hormone (CRH) Precursor Within COS-7 Cells

Journal of Histochemistry & Cytochemistry ◽

10.1177/002215549804601012 ◽

1998 ◽

Vol 46 (10) ◽

pp. 1193-1197 ◽

Cited By ~ 1

Author(s):

Marcelo J. Perone ◽

Simon Windeatt ◽

Ewan Morrison ◽

Andy Shering ◽

Peter Tomasec ◽

...

Keyword(s):

Amino Acid ◽

Golgi Apparatus ◽

Amino Acid Sequence ◽

Protein Secretion ◽

Intracellular Trafficking ◽

Secretory Pathway ◽

Intracellular Localization ◽

Primary Amino Acid Sequence ◽

Releasing Hormone ◽

Primary Amino

We investigated the intracellular localization of CRH in transiently transfected COS-7 cells expressing the full-length rat corticotropin-releasing hormone (CRH) precursor cDNA. CRH synthesized by transfected COS-7 cells is mainly stored intracellularly. In contrast, CHO-K1 cells expressing the same CRH precursor stored and released equal amounts of immunoreactive (IR)-CRH. Ultrastructural analysis revealed that CRH is stored in electron-dense aggregates in the RER of transiently transfected COS-7 cells and does not migrate into the Golgi apparatus. On the basis of the different intracellular localization, storage, and release of CRH in COS-7 and CHO-K1 cells, we hypothesize that the intracellular trafficking of CRH within the constitutive secretory pathway for protein secretion not only depends on its primary amino acid sequence but might also be influenced by intracellular conditions or factors.

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Reactivities of Piperazine-2,5-diones in Radical Bromination Reactions

Australian Journal of Chemistry ◽

10.1071/ch9961229 ◽

1996 ◽

Vol 49 (11) ◽

pp. 1229 ◽

Cited By ~ 3

Author(s):

CLL Chai ◽

DCR Hockless ◽

AR King

Keyword(s):

Crystal Structure ◽

Amino Acid ◽

Chemical Reactivity ◽

Trans Isomers ◽

Radical Bromination ◽

Conformational Effects ◽

Cis And Trans Isomers ◽

The Difference ◽

Cis And Trans

The reactivities of various N,N'- diacetylated piperazine-2,5-diones towards radical bromination reactions are reported. The studies show that glycyl centres of piperazine-2,5-diones are more reactive towards radical bromination reactions compared to α-substituted amino acid centres. In addition, large differences in reactivities were observed for the cis and trans isomers of N,N'-diacetylated alanine anhydride. Single-crystal structure determination of each isomer revealed that conformational effects may account for the difference in chemical reactivity.

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Sequence mutations in teleost cardiac troponin C that are permissive of high Ca2+ affinity of site II

AJP Cell Physiology ◽

10.1152/ajpcell.00339.2002 ◽

2003 ◽

Vol 284 (5) ◽

pp. C1176-C1184 ◽

Cited By ~ 24

Author(s):

Todd E. Gillis ◽

Chris D. Moyes ◽

Glen F. Tibbits

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Amino Acid Sequence ◽

Cardiac Troponin ◽

Troponin C ◽

Fluorescent Reporter ◽

Cardiac Troponin C ◽

The Difference ◽

Higher Sensitivity

Cardiac myofibrils isolated from trout heart have been demonstrated to have a higher sensitivity for Ca2+ than mammalian cardiac myofibrils. Using cardiac troponin C (cTnC) cloned from trout and mammalian hearts, we have previously demonstrated that this comparatively high Ca2+ sensitivity is due, in part, to trout cTnC (ScTnC) having twice the Ca2+ affinity of mammalian cTnC (McTnC) over a broad range of temperatures. The amino acid sequence of ScTnC is 92% identical to McTnC. To determine the residues responsible for the high Ca2+ affinity, the function of a number of ScTnC and McTnC mutants was characterized by monitoring an intrinsic fluorescent reporter that monitors Ca2+ binding to site II (F27W). The removal of the COOH terminus (amino acids 90–161) from ScTnC and McTnC maintained the difference in Ca2+ affinity between the truncated cTnC isoforms (ScNTnC and McNTnC). The replacement of Gln29 and Asp30 in ScNTnC with the corresponding residues from McNTnC, Leu and Gly, respectively, reduced Ca2+ affinity to that of McNTnC. These results demonstrate that Gln29 and Asp30 in ScTnC are required for the high Ca2+ affinity of site II.

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Purification, characterization, gene cloning and preliminary X-ray data of the exo-inulinase from Aspergillus awamori

Biochemical Journal ◽

10.1042/bj3620131 ◽

2002 ◽

Vol 362 (1) ◽

pp. 131-135 ◽

Cited By ~ 30

Author(s):

Michael ARAND ◽

Alexander M. GOLUBEV ◽

J. R. Brandao NETO ◽

Igor POLIKARPOV ◽

R. WATTIEZ ◽

...

Keyword(s):

Amino Acid ◽

Amino Acid Sequence ◽

Solid Phase ◽

Aspergillus Awamori ◽

Glycoside Hydrolase Family ◽

Orthorhombic Space Group ◽

Ph Optimum ◽

X Ray ◽

Cell Parameters ◽

Hydrolysis Of

Extracellular exo-inulinase has been isolated from a solid-phase culture of the filamentous fungus Aspergillus awamori var. 2250. The apparent molecular mass of the monomer enzyme was 69±1kDa, with a pI of 4.4 and a pH optimum of 4.5. The enzyme hydrolysed the β-(2 → 1)-fructan (inulin) and β-(2 → 6)-fructan (levan) via exo-cleavage, releasing fructose. The values for the Michaelis constants Km and Vmax in the hydrolysis of inulin were 0.003±0.0001mM and 175±5μmol·min−1·mg−1. The same parameters in the hydrolysis of levan were 2.08±0.04mg/ml and 1.2±0.02μmol/min per mg, respectively. The gene and cDNA encoding the A. awamori exo-inulinase were cloned and sequenced. The amino acid sequence indicated that the protein belongs to glycoside hydrolase family 32. A surprisingly high similarity was found to fructosyltransferase from Aspergillus foetidus (90.7% on the level of the amino acid sequence), despite the fact that the latter enzyme is unable to hydrolyse inulin and levan. Crystals of the native exo-inulinase were obtained and found to belong to the orthorhombic space group P212121 with cell parameters a = 64.726 Å (1Å = 0.1 nm), b = 82.041 Å and c = 136.075 Å. Crystals diffracted beyond 1.54 Å, and useful X-ray data were collected to a resolution of 1.73 Å.

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Structural features of the low-molecular-mass human salivary mucin

Biochemical Journal ◽

10.1042/bj2870639 ◽

1992 ◽

Vol 287 (2) ◽

pp. 639-643 ◽

Cited By ~ 27

Author(s):

M S Reddy ◽

L A Bobek ◽

G G Haraszthy ◽

A R Biesbrock ◽

M J Levine

Keyword(s):

Amino Acid ◽

Amino Acid Sequence ◽

Molecular Mass ◽

Gel Filtration ◽

Structural Features ◽

Cdna Expression Library ◽

Cdna Clones ◽

Expression Library ◽

Mrna Species ◽

Salivary Mucin

The low-molecular-mass human salivary mucin has at least two isoforms, MG2a and MG2b, that differ primarily in their sialic acid and fucose content. In this study, we characterize further these isoforms, particularly their peptide moieties. Trypsin digests of MG2a and MG2b yielded high- and low-molecular-mass glycopeptides following gel filtration on Sephacryl S-300. The larger glycopeptides from MG2a and MG2b had similar amino acid compositions and identical N-terminal sequences, suggesting common structural features between their peptides. An oligonucleotide probe generated from the amino acid sequence of the smaller glycopeptide from MG2a was employed in Northern-blot analysis. This probe specifically hybridized to two mRNA species from human submandibular and sublingual glands. A cDNA clone selected from a human submandibular gland cDNA expression library with antibody generated against deglycosylated MG2a also hybridized to these two mRNA species. In both cases, the larger mRNA was polydisperse, and the hybridization signal was more intense in the sublingual gland. In addition, the N-terminal amino acid sequence of the larger glycopeptide was found to be part of one of the selected MG2 cDNA clones.

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Amino acid sequence and the cellular location of the Na+-dependent d-glucose symporters (SGLT1) in the ovine enterocyte and the parotid acinar cell

Biochemical Journal ◽

10.1042/bj3120293 ◽

1995 ◽

Vol 312 (1) ◽

pp. 293-300 ◽

Cited By ~ 28

Author(s):

P S Tarpey ◽

I S Wood ◽

S P Shirazi-Beechey ◽

R B Beechey

Keyword(s):

Plasma Membrane ◽

Amino Acid ◽

Amino Acid Sequence ◽

Acinar Cell ◽

Acinar Cells ◽

Amino Acid Sequences ◽

Primary Amino Acid Sequence ◽

Parotid Acinar Cells ◽

Parotid Acinar Cell ◽

Primary Amino

The Na(+)-dependent D-glucose symporter has been shown to be located on the basolateral domain of the plasma membrane of ovine parotid acinar cells. This is in contrast to the apical location of this transporter in the ovine enterocyte. The amino acid sequences of these two proteins have been determined. They are identical. The results indicated that the signals responsible for the differential targeting of these two proteins to the apical and the basal domains of the plasma membrane are not contained within the primary amino acid sequence.

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