Abstract:
:We found that recombinant human adult hemoglobin (rHb A) expressed in Escherichia coli showed heterogeneity of components with the intensity of a positive CD band at 260 nm and that it could be resolved into three components (SP-1, SP-2, and SP-3) by SP-Sepharose column chromatography. 1H NMR revealed that SP-1 is identical with native Hb A, while SP-2 and SP-3 largely contain the reversed heme isomer in both the alpha and beta subunits, with contents of approximately 50 and >80% in SP-2 and SP-3, respectively. Rotation of the heme 180 degrees about the 5,15-meso axis (reversed heme) causes an interexchange of the methyl groups at positions 2 and 7 with the vinyl groups at positions 8 and 3, respectively. To examine the effect of the modification of the heme-protein contact on the structure and function of Hb A, we compared the 1H NMR, CD, and oxygen binding properties of the three components with those of native Hb A. Native Hb A exhibits a distinct positive CD band in both the near-UV and Soret regions, but rHb A with reversed heme exhibits a very weak positive CD band at 260 nm and a prominent negative CD band in the Soret region. Cooperativity, as measured by Hill's n value, decreased from 3.18 (SP-1) to 2.94 (SP-2) to 2.63 (SP-3) with an increase in the reversed heme orientation. The effect of an allosteric effector, inositol hexaphosphate (IHP), on the oxygen binding properties was also reduced in rHb A with reversed heme. These results indicate that changes in the heme-globin contact exert a discernible influence on CD spectra and cooperative oxygen binding.
journal_name
Biochemistryjournal_title
Biochemistryauthors
Nagai M,Nagai Y,Aki Y,Imai K,Wada Y,Nagatomo S,Yamamoto Ydoi
10.1021/bi7015519subject
Has Abstractpub_date
2008-01-15 00:00:00pages
517-25issue
2eissn
0006-2960issn
1520-4995journal_volume
47pub_type
杂志文章相关文献
BIOCHEMISTRY文献大全abstract::The S2 subsite specificity of the plant protease papain has been altered to resemble that of mammalian cathepsin B by site-directed mutagenesis. On the basis of amino acid sequence alignments for papain and cathepsin B, a double mutant (Val133Ala/Ser205Glu) was produced where Val133 and Ser205 are replaced by Ala and ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00101a003
更新日期:1991-09-17 00:00:00
abstract::(E)-4-(4-Chlorophenyl)-2-oxo-3-butenoic acid (CPB) was found to irreversibly inactivate brewers' yeast pyruvate decarboxylase (PDC, EC 4.1.1.1) in a biphasic, sigmoidal manner, as is found for the kinetic behavior of substrate. An expression was derived for two-site irreversible inhibition of allosteric enzymes, and t...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00285a003
更新日期:1983-08-02 00:00:00
abstract::For screening a pool of potential substrates that load carrier domains found in nonribosomal peptide synthetases, large molecule mass spectrometry is shown to be a new, unbiased assay. Combining the high resolving power of Fourier transform mass spectrometry with the ability of adenylation domains to select their own ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi052333k
更新日期:2006-02-14 00:00:00
abstract::To elucidate the enzymatic excision-repair process operative on cyclobutane-type pyrimidine photodimers in human dermal fibroblasts, we have examined excised dimer-containing material recovered in the trichloroacetic acid soluble fraction from far-ultraviolet-irradiated (254 nm, 40 J m-2) and incubated (24 h) cell cul...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00357a055
更新日期:1986-05-06 00:00:00
abstract::Amphotericin B (AmB) is a polyene macrolide antibiotic isolated from Streptomyces nodosus. The antifungal activity of AmB can be attributed to the formation of an ion-channel assembly in the presence of ergosterol (Erg), in which there are two different AmB-Erg orientations, parallel and antiparallel, as reported prev...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/acs.biochem.6b00193
更新日期:2016-06-21 00:00:00
abstract::Many DNA polymerases select their natural substrates, deoxy- as opposed to ribonucleoside triphosphates, with a selectivity greater than 10000-fold. The function of a highly conserved residue, Tyr416, in the palm domain of the parental enzyme, an exo(-) derivative of RB69 DNA polymerase (gp43), a member of the pol alp...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi0202171
更新日期:2002-08-13 00:00:00
abstract::The association of membrane and cytoplasmic proteins with the cytoskeleton of resting and activated platelets was studied. Glycoproteins were identified by labeling with 125I-labeled lectins (concanavalin A, wheat germ agglutinin, and Lens culinaris). Polypeptides, which are embedded in the lipid bilayer, have been id...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00537a002
更新日期:1982-04-13 00:00:00
abstract::A newly recognized type of protein-ligand interaction phenomenon has resulted in the preparation of simple, nonionic, and highly specific gel derivatives for selective adsorption chromatography. The essential structure of the immobilized ligand can be represented as agarose-CH2CH2SO2CH2CH2SCH2CH2OH, which was prepared...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00396a049
更新日期:1987-11-03 00:00:00
abstract::Escherichia coli DNA photolyase mediates photorepair of pyrimidine dimers occurring in UV-damaged DNA. The enzyme contains two chromophores, 1,5-dihydroflavin adenine dinucleotide (FADH2) and 5,10-methenyltetrahydrofolylpolyglutamate (MTHF). To define the roles of the two chromophores in the photochemical reaction(s) ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00485a021
更新日期:1990-08-21 00:00:00
abstract::We have examined the DNA damage produced by reaction of peroxyl radicals with human fibroblast DNA. DNA damage consisted of both strand breaks and base modifications. The extent of strand breaks and base modifications induced as a function of peroxyl radical concentration was determined by quantitation of fragment siz...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi9918994
更新日期:1999-12-14 00:00:00
abstract::The expression level of protein DR1199 is observed to increase considerably in the radio-resistant bacterium Deinococcus radiodurans following irradiation. This protein belongs to the DJ-1 superfamily, which includes proteins with diverse functions, such as the archaeal proteases PhpI and PfpI, the bacterial chaperone...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi800882v
更新日期:2008-11-04 00:00:00
abstract::Avoidance of over-reduction of the chloroplast ferredoxin pool is of paramount importance for plants in avoiding oxidative stress. The redox state of this pool can be controlled through regulation of the thylakoid electron transport chain. A model is presented for regulation of this chain via a thiol reduction mechani...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi027011k
更新日期:2003-03-18 00:00:00
abstract::Eta-crystallin is a retinal dehydrogenase that has acquired a role as a structural protein in the eye lens of elephant shrews, members of an ancient order of mammals. While it retains some activity toward retinal, which is oxidized to retinoic acid, the protein has acquired a number of specific sequence changes that h...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi027367w
更新日期:2003-04-22 00:00:00
abstract::The mechanism of wild-type and R37A mutant Pseudomonas dacunhae aspartate beta-decarboxylase (ABDC) was studied by rapid-scanning stopped-flow spectrophotometry. Mixing wild-type ABDC with 50 mM disodium l-Asp resulted in the formation of a 325 nm absorption peak within the dead time of the stopped-flow instrument, li...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi100272g
更新日期:2010-06-22 00:00:00
abstract::Reporter gene transactivation by human p53 is inhibited in budding yeast lacking the TRR1 gene encoding thioredoxin reductase. To investigate the role of thioredoxin in controlling p53 activity, the level of reporter gene transactivation by p53 was determined in yeast lacking the TRX1 and TRX2 genes encoding cytosolic...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi900757q
更新日期:2009-09-29 00:00:00
abstract::Several snake venoms contain a phospholipase A2 in which position 49 in the active site is occupied by a lysine or a serine instead of the aspartate residue normally found. Although these proteins do not bind Ca2+ and are devoid of catalytic activity, they are still highly specific myotoxins and have recently been sho...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00014a021
更新日期:1995-04-11 00:00:00
abstract::The active site of methionyl-tRNA synthetase (MetRS) possesses two functions: synthetic, which provides Met-tRNA for protein synthesis, and editing, which rejects inadvertently misactivated homocysteine. During editing, the side chain -SH group of homocysteine reacts with its activated carboxyl group forming a cyclic ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi960344v
更新日期:1996-06-25 00:00:00
abstract::The Ca2+-dependent, reversible, interaction of cyclic adenosine 3',5'-monophosphate (cAMP) phosphodiesterase with its activator has been used to purify the enzyme by affinity chromatography. Activator-dependent cAMP phosphodiesterase is only a minor component of the proteins specifically adsorbed in the presence of Ca...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00594a017
更新日期:1978-01-10 00:00:00
abstract::Mutation of Gly90, Glu113, Ala292, and Lys296 in the visual pigment rhodopsin constitutively activates the protein for activation of the G protein transducin. Three of these mutations have been shown to cause two different human diseases. Mutation of Gly90 and Ala292 results in complete night blindness, and mutation o...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00037a035
更新日期:1995-09-19 00:00:00
abstract::Circular dichroism and difference spectroscopy have been used to study dilute aqueous solutions of oxygenated, deoxygenated, and carbamoylated deoxygenated hemoglobins A and S (HbA and HbS, respectively). The spectra of HbA and HbS, in comparable state of oxygenation or carbamoylation, are identical, strongly implying...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00663a022
更新日期:1976-09-07 00:00:00
abstract::A mouse monoclonal IgG1 antibody has been generated against the soluble form of the calmodulin-dependent protein kinase type II. This antibody recognizes both the soluble and cytoskeletal forms of the enzyme, requiring Ca2+ (EC50 = 20 microM) for the interaction. Other divalent cations such as Zn2+, Mn2+, Cd2+, Co2+, ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00417a060
更新日期:1988-08-23 00:00:00
abstract::The aminolysis of the depsipeptide m-[[(phenylacetyl)glycyl]oxy]benzoic acid (1) by D-phenylalanine, catalyzed by the beta-lactamase of Enterobacter cloacae P99, is inhibited by the product of the reaction, (phenylacetyl)glycyl-D-phenylalanine (2), by the peptide analogue of 1, m-[(phenylacetyl)-glycinamido]benzoic ac...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00443a015
更新日期:1989-08-22 00:00:00
abstract::The interaction of the monofunctional chorismate mutase from Bacillus subtilis with chorismate and prephenate has been studied kinetically and by NMR spectroscopy with 13C specifically labeled substrates. Prephenate dominates the population of enzyme-bound species, and the "off" rate constant (approximately 60 s-1) ob...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00489a051
更新日期:1990-09-18 00:00:00
abstract::Fragile X syndrome, the most common cause of inherited mental retardation, is caused by the absence of the fragile X mental retardation protein (FMRP). The emerging picture is that FMRP is involved in repression of translation through a complex network of protein-protein and protein-RNA interactions. Very little struc...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi034909g
更新日期:2003-09-09 00:00:00
abstract::Peptide-membrane interactions are important for understanding the binding, partitioning, and folding of membrane proteins; the activity of antimicrobial and fusion peptides; and a number of other processes. We describe molecular dynamics simulations (10-25 ns) of two pentapeptides Ace-WLXLL (with X = Arg or Lys side c...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi027001j
更新日期:2003-08-05 00:00:00
abstract::The structures of four isomorphous crystals of ternary complexes of chicken heart citrate synthase with D- or L-malate and acetyl coenzyme A or carboxymethyl coenzyme A have been determined by X-ray crystallography and fully refined at 1.9-A resolution. The structures show that both L-malate and D-malate bind in a ver...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00238a028
更新日期:1991-06-18 00:00:00
abstract::Physicochemical properties of recombinant human erythropoietin were examined. This protein, produced in Chinese hamster ovary cells, showed a conformation apparently identical with the natural product isolated from human urine when examined by circular dichroism, UV absorbance, and fluorescence spectroscopy. Sedimenta...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00383a034
更新日期:1987-05-05 00:00:00
abstract::Cysteine dioxygenase (CDO) is a non-heme monoiron enzyme with an unusual posttranslational modification in the proximity of the ferrous iron active site. This modification, a cysteine to tyrosine thioether bond, cross-links two β-strands of the β-barrel. We have investigated its role in catalysis through a combined cr...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi501277a
更新日期:2014-12-23 00:00:00
abstract::A mechanism by which the Klenow fragment of DNA polymerase I monitors the geometry of the base pairs may involve hydrogen bonds between the polymerase and the minor groove of the nascent base pair. The involvement of the 3-position of guanine in the template strand was examined by synthesizing oligodeoxynucleotides co...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi971253g
更新日期:1997-10-28 00:00:00
abstract::Purine repressor (PurR) binding to specific DNA is enhanced by complexing with purines, whereas lactose repressor (LacI) binding is diminished by interaction with inducer sugars despite 30% identity in their protein sequences and highly homologous tertiary structures. Nonetheless, in switching from low- to high-affini...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi0028643
更新日期:2001-07-10 00:00:00