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B Keil

Publications and source records attributed to B Keil.

At least 19 recordsLinked to original sources
PubMed1992

Structural gene and complete amino acid sequence of Vibrio alginolyticus collagenase.

The DNA encoding the collagenase of Vibrio alginolyticus was cloned, and its complete nucleotide sequence was determined. When the cloned gene was ligated to pUC18, the Escherichia coli expression vector, bacteria carrying the gene exhibited both collagenase antigen and collagenase activity. The open reading frame from the ATG initiation codon was 2442 bp in length for the collagenase structural gene. The amino acid sequence, deduced from the nucleotide sequence, revealed that the mature collagenase consists of 739 amino acids with an Mr of 81875. The amino acid sequences of 20 polypeptide fragments were completely identical with the deduced amino acid sequences of the collagenase gene. The amino acid composition predicted from the DNA sequence was similar to the chemically determined composition of purified collagenase reported previously. The analyses of both the DNA and amino acid sequences of the collagenase gene were rigorously performed, but we could not detect any significant sequence similarity to other collagenases.

Amino Acid Sequence↗
PubMed1992

Vibrio alginolyticus ("Achromobacter") collagenase: biosynthesis, function and application.

Bacterial collagenase from aerobic non-pathogenic Vibrio alginolyticus chemovar iophagus ("Achromobacter" collagenase, EC 3.4.24.08) is an inducible extracellular metallo-proteinase. Production of Vibrio collagenase is induced specifically by collagen or by its macromolecular fragments. On the cell surface is expressed a specific receptor recognizing collagen structure. The study of natural inducers led to synthetic peptides with inducing properties. Vibrio collagenase cleaves collagen helical chains preferentially at 3/4 from the N-terminal. Its specific activity on synthetic substrate, 180,000 ukat/mg, represents the highest value for known collagenases. Its specificity differs from that of Clostridium: The enzyme cleaves preferentially sequences with Gly or Ala in position P'1 and Pro in position P2 or P'2. Highly specific cleavages were obtained in beta-casein, prolactin, myosin, adenylate kinase and fibronectin. Autolysis yields partially degraded forms still active on native collagen and peptide substrate. The determination of the sequence of Vibrio collagenase is nearly achieved; the enzyme was not yet obtained in crystalline form. On basis of the already known sequence and structure of Hypoderma collagenase (EC 3.4.21.49), a hypothesis is advanced on the character of collagen binding site loops. Vibrio collagenase can be produced in kilogram quantities at low cost. It was found highly efficient in debridement of necrotic burns, ulcers and decubitus.

Amino Acid Sequence↗
PubMed1991

Subgroup assignment of a human monoclonal anti-Rh(D) antibody.

Variable subgroups of both chains of a human monoclonal anti-RH(D) IgG1 (kappa), QA37C3G6, were determined from their N-terminal sequences. Sequence comparison with corresponding chains of other human antibodies indicated that the light chain belongs to the third subgroup of human kappa-light chains while the heavy chain belongs to the second subgroup of human heavy chains.

Amino Acid Sequence↗
PubMed1991

Partial amino acid sequence of the light chain of human anti-Rh(D) monoclonal antibody H2D5D2F5.

Antibody H2D5D2F5 is a human monoclonal anti-Rh(D) IgG1 (lambda) produced by Epstein-Barr virus-immortalized B lymphocytes from a healthy donor. The complete amino acid sequence of the light (L) chain, with the exception of positions 94-97, was determined by Edman degradation of the intact chain, containing 30 residues, and derived tryptic and thermolytic peptides. Sequences of the peptides were aligned by comparison with the sequences of previously reported L chains. H2D5D2F5 L chain belongs to the first variable subgroup of human chains. Its sequence does not reveal striking differences when compared to those of other human lambda chains issued from myeloma or hybridoma.

Amino Acid Sequence↗
PubMed1991

[Dysfunction in connection with functional disorders of the cervical spine].

In pain patients with functional disorder you can often find a disharmonie in the cervical spine. The results of the examination from 74 patients (47 female, 27 male) shows that: 1. 86.5% of the patients told about neck pain. Those patients with hard neck pain, you can find five or more dolent masticatory muscles. 2. 50% of the patients have on block in the cervical spine, 36.5% have between two and four blocks. 3. In patients with low neck pain you can find less blocks, than in patients with hard neck pain. If there is a block the part of the patients with more than five dolent muscles is significantly higher. 4. 64 patients who have a block shows at the same time 56.8% a functional disorder. So everybody can see that it is really necessary to work together in the diagnosis, therapy and treatment in patients with functional disorders.

Adolescent↗
PubMed1990

Molecular cloning and partial DNA sequencing of the collagenase gene of Vibrio alginolyticus.

DNA fragments Vibrio alginolyticus chemovar iophagus, at least 7 kb in length, were ligated to Escherichia coli expression vectors. Three clones of Escherichia coli HB101 (pLCO-1, pLCO-2, pLCO-3) were obtained by the colony immunoblotting method using anti-collagenase antibody. In Escherichia coli, all these genes produced collagenase antigens which were detected with Western blotting. The amino acid sequence of chemically purified collagenase fragments was also analyzed. An approximately 2.5 kb DNA fragment of the pLCO-1 clone was sequenced, and we found that portions of the deduced amino acid sequence of the chemically analyzed fragments. Therefore, it is highly probable that the gene studied in the present experiment is truly a collagenase structural gene.

Amino Acid Sequence↗
PubMed1990

[The revival of proteinases].

In this article, which was presented at the meeting on proteases (organized by the French Society for Connective Tissue Studies and held in Paris in September 1989) current lines of research on proteases are analyzed. A few examples show that the current renewed interest in this field is the result of qualitatively new facts and ideas.

Databases, Factual↗
PubMed1989

Action of a bacterial Achromobacter collagenase on the soft carious dentine: an in vitro study with the scanning electron microscope.

Samples of carious human teeth treated in vitro for 48-92 hours with a bacterial Achromobacter collagenase in solution in borate buffer at 33 degrees were examined with the scanning electron microscope. The enzyme was seen to destroy soft carious dentine but not sound layers of dentine beneath the lesion. This finding may have clinical implications.

Adult↗
PubMed1988

[Recent data on the structure and function of collagenases].

Four research projects on bacterial and vertebrate collagenases and their therapeutical application are discussed: induction of the production of a bacterial collagenase, proteolytic specificity of the two types of collagenases, their structure-function relations, and the application of the bacterial collagenase in the treatment of burns and ulcers.

Animals↗
PubMed1987

Complete amino acid sequence of the collagenase from the insect Hypoderma lineatum.

The primary structure of the Hypoderma lineatum collagenase was determined. Chymotrypsin digestion and thermolysin fragmentation of the chymotryptic core gave 30 and 5 peptides, respectively, accounting for all the residues of the protein. These peptides were aligned with overlapping peptides derived from tryptic and Staphylococcus aureus V8 proteinase digests. Hypoderma collagenase is a serine proteinase composed of 230 amino acids (Mr 25,223). It displays a high degree of sequential homology with the serine proteinases of the trypsin family, especially with another collagenolytic enzyme, the proteinase I of the crab Uca pugilator. The six half-cystinyl residues of Hypoderma collagenase correspond to 6 of the 10 half-cystinyl residues of chymotrypsin, and the residues forming the charge-relay system of the active site of chymotrypsin (His-57, Asp-102, and Ser-195) are found in corresponding regions. The prediction of the secondary structure of the collagenase is given.

Amino Acid Sequence↗
PubMed1987

Proteolysis Data Bank: specificity of alpha-chymotrypsin from computation of protein cleavages.

The specificity of alpha-chymotrypsin was determined by computation of data retrieved from the Proteolysis Data Bank. The coefficients Kn enable the calculation of the relative influence of the neighbouring amino acid residues in subsites P3--P'3 on the probability of cleavage of polypeptide substrates. The extent of the fixation sites of chymotrypsin and pepsin are compared. The results of the study indicate that predictions of cleavage by proteolytic enzymes can be made from the sequence of polypeptide substrates, provided that a sufficient pool of experimental data has been collected.

Amino Acid Sequence↗
PubMed1987

Databases in molecular biology: a CODATA task group at work.

A certain concern exists that the exponential growth of nucleic acid and protein sequence data will saturate the channels of data acquisition, distribution and utilization on the one hand and, on the other hand, that even the actual resources are still not fully and easily accessible to any bench scientist. Despite the stake of the scientific community at large in the fundamental data collected in this field, there has been in past years only a modest effort to discuss the common problems at an international level. Three international meetings were organized in 1987 on this subject: the annual meeting of CODATA Task Group on Coordination of Protein Sequence Data Banks (Nice, France, January 1987), the EMBL/NIH Workshop concerned primarily with nucleic acid databases (Heidelberg, FRG, February 1987) and the CODATA Workshop on Nucleic Acid and Protein Sequencing Data (Gaithersburg, USA, May 1987).

Amino Acid Sequence↗
PubMed1986

[Structure and properties of animal and bacterial collagenases].

Everywhere is found collagen, collagenases are also found. The author reviews the properties of these collagenases: structure, biosynthesis, activity, inhibition. The therapeutical applications are also discussed. They seem promising since a collagenase I, Achromase can be industrially produced and has been shown interesting both in laboratory studies and in clinical trials.

Animals↗
PubMed1985

Specificity of the collagenase from the insect Hypoderma lineatum.

Specificity of the collagenase from the larvae Hypoderma lineatum, a serine protease related to trypsin, has been investigated by using native collagen and non-collagenous substrates. At 25 degrees C and neutral pH the degradation of collagen by the larval enzyme in solution results in a 52% loss of specific viscosity, without loss of helicity. Electron microscopy of segment-long-spacing crystallites of the digest shows the occurrence of one cleavage region between bands 41 and 44 whereas Edman degradation indicates several cleavage loci in this region. Hypoderma collagenase differs from proteinases I and II from the crab Uca pugilator, which catalyse cleavages in multiple regions of the collagen molecule, and also from vertebrate collagenases, which cleave collagen only between residues 775 and 776. Apart of specific action on collagen, Hypoderma collagenase degrades the oxidized chain B of insulin; the major cleavage occurs at the Leu15-Tyr16 bond followed by two minor cleavages at the Arg22-Gly23 and Lys29-Ala30 bonds. The larval enzyme has no action on synthetic peptide substrates of trypsin or chymotrypsin.

Amino Acid Sequence↗
PubMed1985

Collagenase in mineralized tissues of human teeth.

A collagenase cleaving native type I [14C]collagen but inactive against the synthetic substrate Pz-Pro-Leu-Gly-Pro-D-Arg was extracted from mineralized human dental tissue. The enzyme specifically degrades native collagen into characteristic products (3/4) and (1/4). Its apparent molecular mass of 68 kDa is relatively high in comparison with collagenases from other oral tissues. The enzyme is a metalloproteinase inhibited by low concentrations of the chelating agents EDTA, 1, 10-phenanthroline, alpha alpha'-dipyridyl, and not affected by diisopropylfluorophosphate, soybean trypsin inhibitor, and p-chloromercuribenzoate. It is stable to lyophilization and can be stored at-20 degrees C for at least 6 months.

2,2'-Dipyridyl↗
PubMed1984

Primary structure of alpha-clostripain light chain.

The primary structure of light chain of alpha-clostripain was determined by sequence analysis of peptides derived from tryptic digests purified by reverse-phase high-performance liquid chromatography. The 22 isolated tryptic peptides were aligned by peptides derived from chymotryptic and staphylococcal V8 proteinase digests. The light chain contains 133 amino acids residues and has a relative molecular mass of 15400. The prediction of its secondary structure is given.

Amino Acid Sequence↗