Abstract:
:The relationship between structure, activity, and stability of the thermostable Bacillus stearothermophilus alpha-amylase was studied by site-directed mutagenesis of the three most conserved residues. Mutation of His-238 to Asp involved in Ca2+ and substrate binding reduced the specific activity and thermal stability, but did not affect the pH and temperature optima. Replacement of Asp-331 by Glu in the active site caused almost total inactivation. Interestingly, in prolonged incubation this mutant enzyme showed an altered end-product profile by liberating only maltose and maltotriose. Conservative mutation of the conserved Arg-232 by Lys, for which no function has yet been proposed, resulted in lowered specific activity: around 12% of the parental enzyme. This mutant enzyme had a wider pH range but about the same temperature optimum and thermal stability as the wild-type enzyme. Results obtained with different mutants were interpreted by computer aided molecular modeling.
journal_name
J Biochemjournal_title
Journal of biochemistryauthors
Vihinen M,Ollikka P,Niskanen J,Meyer P,Suominen I,Karp M,Holm L,Knowles J,Mäntsälä Pdoi
10.1093/oxfordjournals.jbchem.a123037subject
Has Abstractpub_date
1990-02-01 00:00:00pages
267-72issue
2eissn
0021-924Xissn
1756-2651journal_volume
107pub_type
杂志文章abstract::The functional activities of myosin head are located in a 95 kilodalton (kDa) heavy chain which can be divided into three fragments of 23 kDa, 50 kDa, and 20 kDa. ATP hydrolysis sites were suggested to be located in the 23 kDa and 50 kDa fragments, and actin binding sites were in the 50 kDa and 20 kDa fragments. In th...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a122292
更新日期:1988-03-01 00:00:00
abstract::The effect of synthetic polycations, polyallylamine, and polyethylenimine, on liposomes containing phosphatidylserine was investigated along with that of polylysine and divalent cations. The addition of polycations caused aggregation of sonicated vesicles composed of phosphatidylserine and phosphatidylcholine (molar r...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a121806
更新日期:1986-10-01 00:00:00
abstract::Purothionin isolated from commercial wheat flour contained several components and two of them (A-I and A-II) were isolated in pure form by CM-52 column chromatography. Each component contained 45 amino acid residues with a 4 disulfide bonds. Purothionin A-II was digested with trypsin and thermolysin to isolate cystine...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a132079
更新日期:1978-06-01 00:00:00
abstract::Peroxiredoxin from Pyrococcus horikoshii (PhPrx) is a decameric protein formed by ring-type assembly of five dimers. To engineer the quaternary structure of PhPrx, we created a mutant PhPrx (PhPrx6m) by introducing six point mutations designed to dissociate PhPrx into dimers. Although PhPrx6m was a dimer in solution, ...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/jb/mvx045
更新日期:2017-12-01 00:00:00
abstract::When the competitive inhibitor benzeneboronic acid (BBA) forms a complex with alpha-chymotrypsin [EC 3.4.21.1] protons are released in the acidic pH region. The proton release can be measured by a difference potentiometric technique. The proton release is also observed in chymotrypsinogen A but not in TRCK-, DIP-, and...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a131036
更新日期:1976-01-01 00:00:00
abstract::High mobility group (HMG) protein 1 contains two DNA binding motifs, called HMG1/2-boxes, linked with a linker region. The functional relationships between the two boxes and the mechanism of involvement of the linker region for effective binding of HMG1 were examined. The binding analyses of truncated HMG1 peptides wi...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a022300
更新日期:1999-02-01 00:00:00
abstract::We previously reported that DNAs directly applicable to restriction analyses and transformation of Escherichia coli can be extracted from fungi and yeasts by use of anhydrous hydrogen fluoride (HF) under a mild condition, 5 min at 0 degrees C [Oshiro, S., Katsura, N., Kitada, K., and Gunge, N. (1987) FEBS Lett. 220, 3...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a124732
更新日期:1995-03-01 00:00:00
abstract::Recently, we revealed that microtubule-associated protein (MAP) 4 isoforms, which differ in the number of repeat sequences, alter the microtubule surface properties, and we proposed a hypothesis stating that the change in the surface properties may regulate the movements of microtubule motors [Tokuraku et al. (2003) J...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/jb/mvm063
更新日期:2007-04-01 00:00:00
abstract::To examine whether serine proteases of rat liver chromatin are also involved in the degradation of newly synthesized and unbound ribosomal proteins and histones, like the nuclear thiol protease which we reported previously (Tsurugi, K. & Ogata, K. (1979) Eur. J. Biochem. 101, 205-213), in vivo experiments were carried...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a134257
更新日期:1983-05-01 00:00:00
abstract::Soybean Bowman-Birk inhibitor, a double-headed inhibitor of trypsin and alpha-chymotrypsin, was treated with cyanogen bromide and then pepsin to yield two inhibitory active fragments. Structural investigation showed that one of the fragments was derived from the trypsin inhibitory domain and the other from the chymotr...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a131968
更新日期:1978-03-01 00:00:00
abstract::The sugar chain of bovine pancreatic ribonuclease B was released from the polypeptide moiety by hydrazinolysis and by endo-beta-N-acetylglucosaminidase H digestion, and reduced with NaB[3H]4 after N-acetylation. The radioactive oligosaccharide mixtures thus obtained were fractionated by Bio-Gel P-4 column chromatograp...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:
更新日期:1980-07-01 00:00:00
abstract::A cytochrome o-type oxidase from the thermophilic bacterium PS3 grown under air-limited conditions was purified by ion-exchange chromatography in the presence of a non-ionic detergent. The enzyme was composed of three subunits (60, 30, and 16 kDa) and seemed to contain two molecules of heme b as prosthetic groups. It ...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a123092
更新日期:1990-04-01 00:00:00
abstract::The complete amino acid sequence of brevilysin H6 (H6), a zinc-protease isolated from Gloydius halys brevicaudus venom, was determined by a manual Edman degradation method. H6 has an amino-terminal pyroglutamic acid and consists of a total of 419 residues. An N-linked sugar chain is attached at Asn-181. The molecule i...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a022737
更新日期:2000-08-01 00:00:00
abstract::The structure of a ferricytochrome c' extracted from Rhodospirillum rubrum has been determined at 6 A resolution by the X-ray crystallographic method. The crystals, obtained by dialyzing the protein solution against polyethylene glycol 4000, belong to the hexagonal space group P6(1). Two heavy atom derivatives were ob...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a135275
更新日期:1985-07-01 00:00:00
abstract::The minimal structural unit of cytochrome c oxidase purified from Thiobacillus novellus was composed of one molecule each of two subunits with molecular masses of 32 and 23 kDa, respectively, and the unit had one molecule of heme a and one atom of copper. In the presence of n-octyl-beta-D-thioglucoside, the oxidase ex...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a123717
更新日期:1992-01-01 00:00:00
abstract::Autoactivation of the proenzyme form of a subunit of the first component (C1r) was performed in the presence and absence of diisopropyl fluorophosphate (DFP). The time-course of autoactivation of zymogen C1r followed a sigmoidal curve and was accelerated by addition of the enzyme C1r and by increasing the concentratio...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a135062
更新日期:1985-01-01 00:00:00
abstract::The kinetics of the hydrogen-deuterium exchange reaction in sarcoplasmic reticulum (SR) membranes isolated from rabbit skeletal muscle was followed by infrared absorption measurements. The exchange rate in SR was much lower than that in the soluble proteins reported so far. When adenylyl-imidophosphate (AMPPNP, an TP ...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a133480
更新日期:1981-08-01 00:00:00
abstract::The cDNA of a novel protein, which contains the association domain of alpha isoform of calmodulin-dependent protein kinase II (CaM-kinase II alpha), was cloned from rat skeletal muscle. This protein, called alpha KAP, consisted of 200 amino acid residues with a molecular weight of 22,583. alpha KAP has a highly hydrop...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a021478
更新日期:1996-10-01 00:00:00
abstract::Daunomycin, an anti-neoplastic agent, is known to be sequestered by acidic organelles in normal and multidrug-resistant cells [Willingham, M.C., Cornwell, M.M., Cardarelli, C.O., Gottesman, M.M., & Pastan, I. (1986) Cancer Res. 46, 5941-5946]. We studied the mechanism of accumulation of daunomycin into acidic organell...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a124320
更新日期:1994-02-01 00:00:00
abstract::An acid proteinase different from pepsin was purified from bullfrog (Rana catesbeiana) gastric mucosa by chromatography on hydroxyapatite, Q-Sepharose, Con A-Sepharose 4B, and Mono Q columns. Its molecular weight after purification was estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis to be 45 kDa...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a124308
更新日期:1994-01-01 00:00:00
abstract::To investigate the role of the C-terminal region of barley beta-amylase, plasmid delta 54 was constructed with an expression vector (pBETA92) of barley beta-amylase by site-directed mutagenesis. Escherichia coli JM109 harboring plasmid delta 54 was expected to express delta 54 beta-amylase in which 54 amino acid resid...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a124722
更新日期:1995-01-01 00:00:00
abstract::When meso-tetrakis(3-N-methylpyridiniumyl)porphyrin (m-TMPyP) formed a complex with poly[d(A-T)(2)], an intense bisignate excitonic CD in the Soret absorption region was observed. The excitonic CD of the m-TMPyP-poly[d(A-T)(2)] complex is unique in that no other combination of the related porphyrin, namely, meso-tetra...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/jb/mvg046
更新日期:2003-03-01 00:00:00
abstract::We examined the inhibitory effect of three pseudo-aminosugars (validamine, valienamine, and valiolamine), which were isolated from the broth of Streptomyces hygroscopicus, on the oligosaccharide-processing glucosidases I and II involved in glycoprotein biosynthesis in rat liver. Both glucosidases I and II were inhibit...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a123160
更新日期:1990-07-01 00:00:00
abstract::Tryptophan residues in ribonuclease from a Rhizopus sp. (RNase Rh) were modified by NBS, H2O2-dioxane, o-nitrophenylsulfenyl chloride (NPS-Cl) and the relation between the extent of modification and enzymatic activity was studied in each case. By extrapolation of the modified tryptophan residue-enzymatic activity curv...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:
更新日期:1980-04-01 00:00:00
abstract::The Escherichia coli cytochrome bo is a heme-copper terminal ubiquinol oxidase, and functions as a redox-driven proton pump. We applied pulse radiolysis technique for studying the one-electron reduction processes in the Cu(B)-deficient mutant, His333Ala. We found that the Cu(B) deficiency suppressed the heme b-to-heme...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/jb/mvp026
更新日期:2009-05-01 00:00:00
abstract::Rat and mouse cDNAs for Zn-alpha 2-glycoprotein (Zn alpha 2gp) were isolated from liver libraries (lambda gt11) and compared with the human one. The lengths of cDNA inserts analyzed were 1,233 and 1,273 nucleotides for rat and mouse, respectively. The deduced amino acid sequences suggested that rat and mouse Zn alpha ...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a124579
更新日期:1994-09-01 00:00:00
abstract::Soluble guanylate cyclase (sGC) consisting of two different subunits (alpha: Mr = 74,000, beta: Mr = 69,000) was purified more than 12,000-fold in terms of specific activity from the supernatant of bovine lung homogenates and characterized. The heme content determined with the pyridine hemochromogen method and Bradfor...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a021785
更新日期:1997-09-01 00:00:00
abstract::To investigate the fine substrate specificities of four highly purified exo-type cellulases (Exo-A from Aspergillus niger, CBHI and CBHII from Trichoderma reesei, and Ex-1 from Irpex lacteus), water-soluble substrates such as barley glucan, xyloglucan from tamarind (Tamarindus indica L.), and their oligosaccharides we...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a021531
更新日期:1996-12-01 00:00:00
abstract::Calmodulin-dependent protein kinase IV (CaM-kinase IV) kinase was recently discovered in the rat brain by its activity to activate the inactive recombinant CaM-kinase IV expressed in Escherichia coli [Okuno, S. and Fujisawa, H. (1993) J. Biochem. 114, 167-170]. In the present study, CaM-kinase IV kinase was purified a...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a124617
更新日期:1994-10-01 00:00:00
abstract::A new method was developed for extracting natural actomyosin with full length connectin (titin) and nebulin from rabbit skeletal muscle. To determine the protein components of native thin filaments, thin filaments were isolated from natural actomyosin by sedimentation in a H2O/D2O/sucrose density gradient. Both alpha-...
journal_title:Journal of biochemistry
pub_type: 杂志文章
doi:10.1093/oxfordjournals.jbchem.a124924
更新日期:1995-08-01 00:00:00