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W Machleidt

Publications and source records attributed to W Machleidt.

At least 73 records · Page 4Linked to original sources
PubMed1985

Amino acid sequence of the intracellular cysteine proteinase inhibitor cystatin B from human liver.

The complete amino acid sequence of the cysteine proteinase inhibitor cystatin B (formerly named CPI-B) from human liver was determined. The 98-residue sequence (Mr = 11,175) was obtained by automated solid-phase Edman degradation of a large cyanogen bromide fragment and peptides generated by enzymatic cleavage. The protein starts with a blocked Met-Met sequence which is presumably N-acetylated. The sequence shows that human cystatin B is a member of the family of intracellular cystatins; it is 79% identical with cystatin beta from rat liver, but contains only a single cysteine. Human cystatin B is able to form a dimer stabilized by noncovalent forces.

Amino Acid Sequence↗
PubMed1985

Identification of the polypeptide encoded by the URF-1 gene of Neurospora crassa mtDNA.

Two peptides, potentially representing antigenic determinants of a proposed gene product, were synthesized. The peptide sequences were deduced from the nucleotide sequence of the unidentified reading frame (URF)1 of the Neurospora crassa mitochondrial genome. Specific antisera to the synthetic peptides were produced. The antibodies recognized a single polypeptide species with an apparent relative molecular mass of about 30 000. The mitochondrial origin of this polypeptide was verified by in vivo labelling experiments in the presence of cycloheximide, as well as by in vitro translation using isolated mitochondria. The chemical identification of the protein was performed by partial radiosequencing of the N-terminal portion of the immunoprecipitated URF-1 product. The amount of URF-1 polypeptide present in N. crassa mitochondria is in the range of 1-2%. The protein is a constituent of the inner envelope of the organelle and probably part of a more complex membrane unit.

Amino Acid Sequence↗
PubMed1985

Human plasma kininogens are identical with alpha-cysteine proteinase inhibitors. Evidence from immunological, enzymological and sequence data.

Human high- and low-Mr kininogens were shown to be potent inhibitors of cysteine proteinases such as cathepsin L and papain (Ki = 17-48 pM). A strong immunological cross-reaction between the kininogens and low-Mr alpha-cysteine proteinase inhibitor from human plasma was found. Comparison of partial amino acid sequences from high- and low-Mr kininogen and low-Mr alpha-cysteine proteinase inhibitor demonstrated sequence identity for all segments analyzed. These findings suggest that the kininogens and the alpha-cysteine proteinase inhibitors from human plasma are identical proteins.

Amino Acid Sequence↗
PubMed1985

Amino acid sequence of human liver cathepsin B.

The complete amino acid sequence of cathepsin B (EC 3.4.22.1) from human liver was determined. The 252-residue sequence was obtained by automated solid-phase Edman degradation of the light and heavy chain resulting from limited proteolysis of the single-chain enzyme and of fragments produced by cyanogen bromide and enzymatic cleavage of the heavy chain. Human liver cathepsin B has 83.7% identical residues with the corresponding enzyme from rat liver. Comparison of both mammalian cathepsin B sequences with the sequence of papain provides further evidence that lysosomal and plant cysteine proteinases have evolved from a common ancestor and share a similar catalytic mechanism.

Amino Acid Sequence↗
PubMed1984

Human cystatin, a new protein inhibitor of cysteine proteinases.

A new low-molecular weight protein inhibitor of cysteine proteinases, human cystatin, was isolated from sera of patients with autoimmune diseases. It inhibits papain, human cathepsin H and cathepsin B. According to its partially determined amino-acid sequence, human cystatin is highly homologous to egg white cystatin, but only distantly related to stefin, the cytosolic protein inhibitor of cysteine proteinases isolated from human polymorphonuclear granulocytes. Very probably human cystatin is identical with human gamma-trace, a microprotein of known sequence but hitherto unknown function.

Amino Acid Sequence↗
PubMed1984

[Ultradian periodicity, diurnal and circannual rhythms in the electroencephalogram].

The cerebral rhythms depictable by the EEG show fluctuations with several characteristic periodicities. The ultradian region with a range from several seconds to 20 hours is divided into three sections. Pathological and physiological EEG-characteristics are influenced by physiological rhythms of 2-100 seconds. The EEG-complexes occurring with panencephalitis are dependent on breath frequency. Grouped dysrhythmias correlate with higher order blood pressure waves. Systematic changes of the basal activity caused by slow variations of direct voltage have been conjectured by Aladzhalova (1964) and confirmed by spectral analysis (K unkel et al. 1969). Periods of 60-140 minutes with a medium cycle of approximately 90 minutes are typical for sleep, the phases of which are shown by the EEG and the recording of rapid eye movements (REM). THe periodicity corresponding to the basic rest activity cycle can also be shown on the EEG in a state of awakeness . Diurnal studies between sunrise and sunset showed frequency variations of some pathological EEG characteristics. The frequency of abnormal rhythms increased evenly from 8 am to 3.8% to 3 pm to 9.5%. Grouped dysrhythmias showed similar effects. As far as basal activity is concerned the occurrence of a diurnal peak of measurements in the alpha range and their maxima in the high frequency ultradian regions was noticeable. Circadian studies with a periodicity of 24 (plus/minus 4) hours showed that the diurnal maxima of all frequency ranges occurred almost simultaneously, however, they contained temporal shifts due to their specific structure. The major pertinent differences were shown by frontal and temporobasal cerebral areas. Circadian studies of sleep phases of primates showed a maximum for delta activity at 1 am and for theta activity at 5 am. As expected, circannual rhythms of hibernating animals can be observed on the EEG, they have also been discovered with humans be means of EEG measurements: by visually analyzing EEG results, systematic differences in the frequency of types of basal activity were noticed. Thus, Beta-EEGs with a medium frequency of 14% occurred in May with the frequency of Alpha-EEGs fluctuated in inverse proportion and was at its peak during summer. Conspicuous among pathological EEG characteristics were grouped dysrhythmias that occurred about twice as often in summer as in winter. No generally valid cause can be assumed for the variety of rhythms.

Alpha Rhythm↗
PubMed1984

On the synthesis of a 32P-labelled Edman reagent for the sensitive identification of amino-acid derivatives.

A phosphorus-32 containing derivative of phenylisothiocyanate was prepared to increase the sensitivity of amino-acid sequence determination. The respective compound 2-(4-isothiocyanatophenoxy)-1,3,2-dioxaphosphinane 2-oxide showed about the same reactivity, stability, and polarity as the Edman reagent itself. A repetitive yield of 94% was obtained in the stepwise degradation of insulin B chain using a solid phase sequencer. The synthesis of this radioactive reagent was achieved within 5 h but with a specific activity of 1 Ci/mol. Eight amino acids were reacted with the 32P-labelled reagent and identified by autoradiography after two dimensional thin-layer chromatography.

Amino Acid Sequence↗
PubMed1983

Protein inhibitors of cysteine proteinases. I. Isolation and characterization of stefin, a cytosolic protein inhibitor of cysteine proteinases from human polymorphonuclear granulocytes.

A protein inhibitor of cysteine proteinases, "stefin", was purified from cytosol of human polymorphonuclear granulocytes. Affinity chromatography on carboxymethylated papain-Sepharose was used as the first step, followed by ion exchange chromatography on DEAE-Sephacel, which resolved four inhibitory peaks. The main peak, comprising approx. 80% of total inhibitory activity was characterized. It was found to be a homogenous protein with an apparent molecular mass slightly lower than that of cytochrome c and with an isoelectric point of 4.65. The inhibitor inhibits papain at a molar ratio of 1:1 as well as cathepsin B and H, but it does not inhibit serine and aspartic proteinases. It is stable at elevated temperature and in alkaline pH, but looses its activity in acid pH. Oxidized glutathione has no effect on its inhibitory activity.

Chromatography, Affinity↗
PubMed1983

Protein inhibitors of cysteine proteinases. II. Primary structure of stefin, a cytosolic protein inhibitor of cysteine proteinases from human polymorphonuclear granulocytes.

The primary structure of stefin, a new cysteine proteinase inhibitor from the cytosol of human polymorphonuclear granulocytes, was determined by amino-acid sequence analysis. The protein consists of 98 amino-acid residues and contains no cysteine. Its molecular mass was calculated to be 11006 Da. The sequence was obtained by automatic solid-phase Edman degradation of the uncleaved protein and its cyanogen bromide fragments. There is no striking evidence for a sequence homology with known families of protein inhibitors of proteinases.

Amino Acid Sequence↗
PubMed1983

Protein inhibitors of cysteine proteinases. III. Amino-acid sequence of cystatin from chicken egg white.

Cystatin, the protein inhibitor of cysteine proteinases from chicken egg white was purified by a new method. The two major forms with pI 6.5 (Peak I) and 5.6 (Peak II) were separated. Molecular masses of both forms are approx. 12700 Da as determined by gel chromatography; Form A from Peak I has a molecular mass of 12191 Da as calculated from its amino-acid sequence. The complete amino-acid sequence of Form A was determined by automated solid-phase Edman degradation of the whole inhibitor and its cyanogen bromide fragments. It contains 108 amino-acid residues. Form B from Peak II represents an elongation of Form A by 8 amino-acid residues at the N-terminus. Cystatin contains four cysteine residues, presumably forming two disulphide bridges. Comparison of the amino-acid sequences and near ultraviolet circular dichroism spectra of stefin, the cysteine proteinase inhibitor from human granulocytes, and cystatin shows that the two proteins are entirely different. According to the primary structures, probably neither proteinase inhibitor is involved in a thiol-disulphide exchange mechanism in the interaction with its target enzyme.

Amino Acid Sequence↗
PubMed1983

Amino-acid sequence of the smallest protein of the cytochrome c1 subcomplex from beef heart mitochondria.

A cytochrome c1 subcomplex was obtained from purified complex III. The subcomplex consists of three protein subunits, present at an equimolar stoichiometry. The primary structures of two of these proteins, the heme-carrying cytochrome c1 and a protein with a molecular mass of 9175 Da, have been published by Wakabayashi et al. The covalent structure of the smallest subunit is presented in this paper. This protein consists of 62 amino acid residues; its molecular mass was calculated to be 7189 Da. The sequence was determined by complete solid-phase Edman degradation of the uncleaved polypeptide and was confirmed by sequencing the C-terminal fragment resulting from cleavage of a single tryptophyl bond.

Amino Acid Sequence↗
PubMed1983

[Circadian, infradian and seasonal changes in neural conduction velocity with reference to effects of temperature; I.: Circadian rhythm].

Using results of two collectives (one cross-section study covering 212 individuals and a longitudinal study of 10 individuals over a period of 4 days with 4 examinations/individual/day) circadian, infradian and seasonal influences on the changes observed are considered. The skin temperatures displayed significant circadian variations subsequent to electrical stimulation in 4 of 5 topographic regions from which the measurements were performed. Before stimulation in only one of five regions significant circadian changes were observed. Thus stimulation caused an increase in amplitude but no changes in phase. Pre- and post-stimulation rhythms were in phase. There was found a two-peaked circadian rhythm with maxima at late noon and at midnight. Probably there were systematic differences in skin temperature in the upper extremities compared to the lower ones. The latter showed a minimum in the early morning hours. The circadian effects are presented almost completely free of temperature influences for the sensory NCV of the n. medianus on the hand. As opposed to the simultaneously acquired 2-peaked circadian rhythm of the skin temperature an almost continuous decrease in the NCV can be observed from the early morning until midnight. After midnight there was an abrupt increase of the NCV by about 5%. The significant influences of the time-of-day on the NCV of the upper- and lower-arm could not be attained independent of temperature influences. It was nonetheless apparent that the motor and sensory NCV of the lower arm increased throughout the day in contrast to the NCV of the hand. Possibly, local' influences interfered thereby with the autonomic rhythm of the nerve.

Adolescent↗
PubMed1983

[Circadian, infradian and seasonal changes in neural conduction velocity with reference to the effects of temperature. II: Infradian and seasonal changes].

Using the longitudinal study it was shown that a number of sensory neurographic parameters changed systematically throughout the 4-day investigation. In particular the sensory NCV of the n. medianus of the hand increased significantly. Possible causes i.e. the activation of the metabolism are discussed. Should this assumption prove to be true repetitive stimulation of a nerve could have a therapeutic effect. The seasonal influences are displayed using the results of a cross-sectional study. Six out of 21 neurographic parameters showed significant seasonal variations. In the NCVs of the n. medianus and the n. ulnaris maxima were present in summer and autumn while the NCVs of the lower extremities had minima. In winter and spring differences between the NCVs of the lower and upper arm and leg were lowest. These differences may be caused by seasonal changes of the metabolism which modifies the coefficient of the temperature of the neurographic parameters.

Circadian Rhythm↗
PubMed1982

Subunit 1 of cytochrome oxidase from Neurospora crassa: nucleotide sequence of the coding gene and partial amino acid sequence of the protein.

A partial protein sequence (223 residues) of cytochrome oxidase subunit 1 from Neurospora crassa has been established. The nucleotide sequence of a cloned mitochondrial DNA segment, including the structural gene coding for the mature subunit 1 (CO I locus) was determined. In contrast to the situation in yeast, the CO I locus in N. crassa is not interrupted by long intervening sequences. A polypeptide of 555 residues with a mol. wt. of 61 000 has been deduced from the reading frame established by protein sequencing. With the exception of the C-terminal part of the polypeptide, the proposed sequences for subunit 1 of N. crassa, yeast, and man are largely homologous. Protein sequencing reveals that a region of low homology close to the C-terminal portion belongs to the structural gene in N. crassa. The DNA sequence coding for the prepiece , which characterizes the polypeptide precursor of the N. crassa subunit 1, has not yet been localized. A RNA species of approximately 6.8 kb has been identified as the CO I transcript. There is no indication of splicing of this large transcript.

Amino Acid Sequence↗
PubMed1980

N,N'-dicyclohexylcarbodiimide binds specifically to a single glutamyl residue of the proteolipid subunit of the mitochondrial adenosinetriphosphatases from Neurospora crassa and Saccharomyces cerevisiae.

The N,N'-dicyclohexylcarbodiimide-binding proteolipid subunit of the mitochondrial adenosinetriphosphatases (ATP phosphohydrolase, EC 3.6.1.3) of Neurospora crassa and Saccharomyces cerevisiae were purified from mitochondria incubated with the radioactively labeled inhibitor. The specifically labeled subunit was cleaved with cyanogen bromide and N-bromosuccinimide, and the resultant fragments were separated by gel chromatography in the presence of 80% (vol/vol) formic acid. The N,N'-dicyclohexylcarbodiimide label was recovered in each organism exclusively in a 17-residue fragment. Further analysis by automated solid-phase Edman degradation revealed that the bound label was present at only one position, corresponding to a glutamyl residue. The N,N'-dicyclohexylcarbodiimide-modified glutamyl residue is the only identical acidic position in both proteins and occurs in the middle of a hydrophobic sequence of about 25 residues.

Adenosine Triphosphatases↗