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J E Fothergill

Publications and source records attributed to J E Fothergill.

At least 19 recordsLinked to original sources
PubMed1998

Human matrix metalloproteinase-9: activation by limited trypsin treatment and generation of monoclonal antibodies specific for the activated form.

For many studies on matrix metalloproteinases in immunohistochemistry it is important to be able to distinguish between the zymogen and activated forms of the enzymes. Activated human matrix metalloproteinase-9 (MMP-9, gelatinase B) was produced from the proenzyme by limited digestion with trypsin. The products of cleavage were characterised by SDS/PAGE and N-terminal sequencing. Trypsin treatment led to a stepwise removal of the propeptide domain and also caused cleavage within the C-terminal domain. Monoclonal antibodies specific for the activated form of human MMP-9 were raised by using a peptide corresponding to the N-terminus of the activated enzyme as immunogen. The antibodies do not recognise the MMP-9 proenzyme or the active or proenzyme forms of matrix metalloproteinase-2 (MMP-2, gelatinase A) and do not react with unrelated proteins in an unfractionated tissue extract. The antibodies were used to detect, by immunohistochemistry, activated MMP-9 in formalin-fixed, wax-embedded sections from a series of oesophageal cancer cases previously shown to contain MMP-9. All of the tumours contained activated MMP-9 localised to tumour cells and macrophages. As the antibodies are effective in immunohistochemistry on formalin-fixed, wax-embedded sections, they should prove useful for the detection of activated MMP-9 in various disease processes.

Amino Acid Sequence↗
PubMed1998

Matrix metalloproteinase-1 is associated with poor prognosis in oesophageal cancer.

The matrix metalloproteinases (MMPs) are a family of closely related proteolytic enzymes which are involved in the degradation of different components of the extracellular matrix. There is increasing evidence to indicate that individual MMPs have an important role in tumour invasion and tumour spread. Monoclonal antibodies specific for MMP-1, MMP-2, or MMP-9 have been produced, using as immunogens peptides selected from the amino acid sequences of individual MMPs. The presence of MMP-1, MMP-2, and MMP-9 in oesophageal cancer was investigated by immunohistochemistry on formalin-fixed, wax-embedded sections of oesophageal cancers. The relationship of individual MMPs to prognosis and survival was determined. MMP-1 was present in 24 per cent of oesophageal cancers, while MMP-2 and MMP-9 were present in 78 and 70 per cent of tumours, respectively. The presence of MMP-1 was associated with a particularly poor prognosis (log rank test 8.46, P < 0.004) and was an independent prognostic factor (P = 0.02). The identification of individual MMPs in oesophageal cancer provides a rational basis for use in the treatment of oesophageal cancer of MMP inhibitors which are currently undergoing clinical trial.

Adenocarcinoma↗
PubMed1998

Matrix metalloproteinases and their inhibitors in gastric cancer.

BACKGROUND: The matrix metalloproteinases (MMPs) and tissue inhibitors of matrix metalloproteinases (TIMPs) are strongly implicated in tumour invasion and metastasis. AIMS: To investigate the presence of individual MMPs and TIMPs in gastric cancer. METHODS: The presence of MMP-1, MMP-2, MMP-3, MMP-9, TIMP-1, and TIMP-2 was identified in a group of gastric cancers (n=74) by immunohistochemistry using monoclonal antibodies. These antibodies were effective on formalin fixed, paraffin wax embedded sections. RESULTS: A large proportion (94%) of gastric cancers contained MMP-2; MMP-1 and MMP-9 were also detected in 73% and 70% of tumours respectively. MMP-3 was only present in 27% of tumours. MMP-1 and MMP-9 were found predominantly in intestinal type tumours. TIMP-1 and TIMP-2 were identified in 41% and 57% of tumours respectively. Immunoreactivity for individual MMPs or TIMPs was not identified in normal stomach. CONCLUSIONS: This study shows the presence of matrix metalloproteinases, particularly MMP-2, and TIMPs in stomach cancer. Antibodies which are effective in formalin fixed, paraffin wax embedded sections are useful for the identification of MMPs and TIMPs in diagnostic specimens.

Adult↗
PubMed1997

Photoreceptor rim protein: partial sequences of cDNA show a high degree of similarity to ABC transporters.

PURPOSE: To isolate and sequence cDNA for bovine rim protein, a large membrane-bound glycoprotein found in photoreceptor outer segments. METHODS: Bovine rim protein was N-terminally sequenced (22 residues) and fragments were prepared by partial proteolysis. Two internal sequences of 21 and 18 amino acid residues were obtained from 35 kDa and 32 kDa fragments, respectively. Sense and anti-sense oligonucleotide primers were constructed, based on the peptide sequences derived from the 35 kDa and 32 kDa fragments, respectively, and the polymerase chain reaction (PCR) was used to amplify a 150 bp sequence from bovine retinal cDNA. RESULTS: The amplified sequence coded for the remainder of the peptide sequence determined from the 35 kDa fragment, which was not present in the primer, confirming that it was derived from the rim protein. The 150 bp sequence was translated to give a 50 amino acid peptide. Part of this peptide was compared with Dna sequence databases using the TFastA program, which found 94.6% identity with an EST derived from human retina and 86.1% identity to the mouse abc1 transporter. CONCLUSIONS: It is proposed that rim protein is a member of the ATP transporter family of proteins. It may be involved in transport of molecules involved in visual transduction across the photoreceptor disk membrane.

ATP-Binding Cassette Transporters↗
PubMed1996

Matrix metalloproteinase-1 is associated with poor prognosis in colorectal cancer.

Colorectal cancer is one of the commonest malignant tumors and has a relatively poor prognosis. The outcome depends on the extent of local and particularly metastatic tumor spread. The matrix metalloproteinases (MMPs) are a family of closely related enzymes that degrade the extracellular matrix and are considered to be important in facilitating tumor invasion and spread (1-3). Using immunohistochemistry we have investigated the occurrence in colorectal cancer of MMP-1 (interstitial collagenase). Our monoclonal antibody was prepared against a synthetic peptide corresponding to an amino acid sequence specific for MMP-1 and was selected to react in formalin-fixed wax-embedded sections, thus allowing use in diagnostic histopathology and also enabling access to archival material. We found that the presence of MMP-1 in colorectal cancer is associated with a poor prognosis (P = 0.006) and has prognostic value independent of Dukes stage. One MMP inhibitor that strongly inhibits MMP-1 has already been shown to inhibit growth of human colon cancer xenografts in nude mice (4). Our results suggest that treatment of those individuals whose colon tumors produce MMP-1 with MMP inhibitors is a therapeutic strategy worth pursuing.

Animals↗
PubMed1995

A constraint-based assignment system for automating long side chain assignments in protein 2D NMR spectra.

The sequential assignment of protein 2D NMR data has been tackled by many automated and semi-automated systems. One area that these systems have not tackled is the searching of the TOCSY spectrum looking for cross peaks and chemical shift values for hydrogen nuclei that are at the end of long side chains. This paper describes our system for solving this problem using constraint logic programming and compares our constraint satisfaction algorithm to a standard backtracking version.

Automation↗
PubMed1994

The amino acid sequence of the small monomeric phosphoglycerate mutase from the fission yeast Schizosaccharomyces pombe.

The amino acid sequence of the monomeric 2,3-bisphosphoglycerate (BPG)-dependent phosphoglycerate mutase (PGAM) from the fission yeast Schizosaccharomyces pombe has been determined. Amino acid sequencing of proteolytic fragments of the enzyme showed the S. pombe mutase to be similar in sequence to the tetrameric enzyme of baker's yeast (Saccharomyces cerevisiae). An S. pombe cDNA library was screened using a PCR fragment generated from two oligonucleotides complementary to sequences encoding the regions at the two active-site histidine residues. The 0.63 kb cDNA encoded an open reading frame of 210 amino acids. This sequence agreed completely with sequences of peptides derived from the purified protein. The amino acid sequence of S. pombe PGAM is 43% identical with that of S. cerevisiae PGAM and shows an equally high degree of identity with BPG-dependent PGAMs from other sources. However, the sequence of the S. pombe enzyme differs from other BPG-dependent enzymes in three important ways: (i) it does not contain the alanine- and lysine-rich sequence of amino acids at the C-terminus which have been proposed to constitute a flexible tail involved in catalysis; (ii) the sequence spanning residues 122-146 (S. cerevisiae PGAM numbering) is not present in the S. pombe PGAM sequence; in the S. cerevisiae PGAM crystal structure this stretch of sequence has been shown to occur as an extended loop, part of which is involved in inter-subunit interactions; (iii) the amino acid sequence in the region of a second S. cerevisiae inter-subunit contact (residues 74-78) shows radical mutations in the S. pombe enzyme.

Amino Acid Sequence↗
PubMed1993

Complete amino acid sequences of five dimeric and four monomeric forms of metallothionein from the edible mussel Mytilus edulis.

Cadmium-induced metallothioneins from the common sea mussel, Mytilus edulis, were shown to comprise of two groups of isoforms having apparent molecular masses of 10 kDa and 20 kDa. The 10-kDa group was resolved by anion-exchange chromatography into four fractions while the 20-kDa group was resolved into three fractions using this method. After metal removal and S-methylation of the cysteine residues using methyl-p-nitrobenzenesulphonate the complete amino acid sequences were determined. Five isoforms of the 20-kDa group were shown to possess monomeric units consisting of 71 amino acids. These proteins were distinct from the four 72-amino-acid proteins of the 10-kDa group. The FASTA algorithm has been used to compare the degree of similarity between the mussel metallothionein MT-10-IV isoform and other metallothioneins. The mussel MT-10-IV isoform exhibited substantial similarity to other molluscan metallothioneins. Moreover, the mussel metallothionein exhibited more similarity to vertebrate metallothioneins than to those of non-molluscan invertebrates, thus suggesting that the mussel metallothioneins are class I metallothioneins.

Amino Acid Sequence↗
PubMed1993

Immunohistochemistry of neurone specific enolase with gamma subunit specific anti-peptide monoclonal antibodies.

AIMS: To investigate the application in immunohistochemistry of gamma-subunit specific anti-peptide monoclonal antibodies to human neurone specific enolase (NSE); and to determine their reactivity with formalin fixed, wax embedded sections of normal tissue and neuroendocrine tumours. METHODS: Immunohistochemical staining was performed on sections of formalin fixed, wax embedded tissue with two monoclonal antibodies (NSE-P1 and NSE-P2) raised against different synthetic peptides specific for the gamma subunit of human enolase (neurone specific enolase). RESULTS: Both antibodies gave strong immunostaining in normal tissues and cells known to contain NSE. There was no immunoreactivity in tissues containing either the alpha alpha or beta beta isozymes of enolase. The reactivity of the antibodies with a range of neuroendocrine tumours was also studied and both antibodies gave strong immunostaining of tumour cells in the different tumours. CONCLUSIONS: The use of synthetic peptides from defined regions of a molecule as immunogenes provides antibodies of high specificity. These monoclonal antibodies to NSE are ideally suited for immunohistochemical studies and they should be particularly useful in histopathology as they react with epitopes which are resistant to formalin fixation and wax embedding.

Antibodies, Monoclonal↗
PubMed1992

A simple enzyme-linked immunosorbent assay (ELISA) for the neuron-specific gamma isozyme of human enolase (NSE) using monoclonal antibodies raised against synthetic peptides corresponding to isozyme sequence differences.

Monoclonal antibodies specific for the gamma isozyme of human enolase (known as neuron-specific enolase or NSE) have been raised against synthetic peptides after coupling to carrier protein: the selected peptides were those corresponding to regions of amino acid sequence difference between the alpha and gamma subunits of these closely similar isozymes. This technique gave monoclonal antibodies of high specificity and affinity. Two monoclonal antibodies raised against different peptides were used to develop a double-antibody sandwich enzyme-linked immunosorbent assay (ELISA), using one as the solid-phase antibody and the other conjugated to horseradish peroxidase to detect the bound NSE. This assay provides a simple and routine method of detecting NSE in serum samples from patients with small-cell carcinoma of the lung and related tumours.

Amino Acid Sequence↗
PubMed1991

Complete nucleotide sequence of the gene for human C1 inhibitor with an unusually high density of Alu elements.

The complete (17159 bp) nucleotide sequence of the gene for the human C1 inhibitor has been determined. The transcription initiation site was examined by primer extension using human liver mRNA, and the messenger 5'-end sequence was determined on clones obtained by the anchored polymerase chain reaction. The gene of this serpin molecule is split by seven introns, with junctions of phases zero and one. An outstanding feature of the intron sequences is the occurrence of 17 AluI repeats of all four ancestral subgroups, indicating that the gene has been invaded during consecutive waves of Alu amplification, including a recent one. These Alu repeats form the sites of deletion and insertion in several known lesions in the C1-inhibitor gene. There is no obvious promoter site of the TATA-box type at the 5' end of the gene, but instead it contains a region of potential H-DNA structure similar to that found upstream of the human c-myc gene.

Amino Acid Sequence↗
PubMed1990

The plant mitochondrial F1-ATPase. The identity of the delta' (20 kDa) subunit.

The N-terminal amino acid sequence of the 20 kDa (delta') subunit of the turnip (Brassica napus L.) mitochondrial F1-ATPase has been determined. Comparison of the sequence obtained with those of the epsilon subunits of chloroplast CF1, E. coli F1 and the delta subunit of bovine F1 shows that the turnip delta' subunit is another member of this family of homologous proteins. The delta' subunit of sweet potato F1-ATPase [(1989) J. Biol. Chem. 264, 3183-3186] is very similar to the turnip sequence and thus can also be considered to belong to this family.

Amino Acid Sequence↗
PubMed1990

Limited proteolysis of beta 2-microglobulin at Lys-58 by complement component C1s.

We have now demonstrated that activated complement component C1s cleaves beta 2-microglobulin at the position identical to that at which beta 2-microglobulin is cleaved in serum of patients suffering from lung cancer. The main cleavage is in the disulphide loop C-terminal to Lys-58, generating a modified form of beta 2-microglobulin with a two-chain structure. The C-terminal Lys-58 in the A chain is highly susceptible to removal by a carboxypeptidase-B-like activity causing the formation of des-Lys58-beta 2-microglobulin. This is the first demonstration of a noncomplement protein substrate for the proteolytic activity of C1s. The C1s-induced cleavage of beta 2-microglobulin can be inhibited in the presence of C1 esterase inhibitor, demonstrating a regulatory function of C1 esterase inhibitor in the C1s-induced cleavage of beta 2-microglobulin.

Amino Acid Sequence↗
PubMed1990

An object-oriented database for protein structure analysis.

An object-oriented database system has been developed which is being used to store protein structure data. The database can be queried using the logic programming language Prolog or the query language Daplex. Queries retrieve information by navigating through a network of objects which represent the primary, secondary and tertiary structures of proteins. Routines written in both Prolog and Daplex can integrate complex calculations with the retrieval of data from the database, and can also be stored in the database for sharing among users. Thus object-oriented databases are better suited to prototyping applications and answering complex queries about protein structure than relational databases. This system has been used to find loops of varying length and anchor positions when modelling homologous protein structures.

Amino Acid Sequence↗
PubMed1989

Plant mitochondrial F1-ATPase. The presence of oligomycin-sensitivity-conferring protein (OSCP).

Purified pea (Pisum sativum) cotyledon F1-ATPase contains six subunits rather than the five usually reported for F1-ATPases. The additional 26.5 kDa (delta) subunit is shown by immunoblotting and N-terminal amino acid sequencing to be similar to bovine oligomycin-sensitivity-conferring protein (OSCP). It is concluded that the delta subunit of plant mitochondrial F1-ATPase is the plant OSCP. This OSCP subunit occurs in all mono- and di-cotyledonous species of plants tested (maize, oats, peas, potatoes, sweet potatoes and turnips).

Adenosine Triphosphatases↗
PubMed1989

Monocyte C1-inhibitor synthesis in patients with C1-inhibitor deficiency.

Monocytes of seven out of eight patients with type 1 C1-inhibitor (C1-inh) deficiency (HAE) produced 40% as much C1-inh as monocytes from normal donors (controls). In contrast, monocytes from three patients with type 2 and three patients with acquired C1-inh deficiency produced similar amounts of C1-inh as controls. Recombinant gamma-interferon (gamma-interferon 10 ng/ml) stimulated C1-inh production of C1-inh (eight-10-fold) by control and patients' monocytes. Monocytes from patients with type 1 HAE contained 40% the level of C1-inh messenger ribonucleic acid (mRNA) found in control monocytes. Gamma-interferon increased the abundance of C1-inh mRNA by the same extent in both control and patients' monocytes. C1-inh protein and mRNA were undetectable in the monocytes of one patient, unless stimulated by gamma-interferon. Under these conditions, his monocytes produced comparable amounts of C1-inh (protein and mRNA) as gamma-interferon-stimulated monocytes of the other type 1 HAE patients. The data suggest that in most type 2 HAE patients there is a lesion in the C1-inh gene such that mRNA is transcribed by a single allele.

Angioedema↗
PubMed1988

Complete amino acid sequence of the neurone-specific gamma isozyme of enolase (NSE) from human brain and comparison with the non-neuronal alpha form (NNE).

The complete amino acid sequence (433 residues) of the human neurone-specific gamma isozyme of enolase (NSE) has been determined by a combination of direct amino acid sequencing and nucleotide sequencing of cloned cDNA. Substantial amino acid sequence of the non-neuronal alpha form of the enzyme was also obtained which agreed almost entirely with the indirect cDNA sequence. Comparison of the two human sequences shows no insertions or deletions, but 72 replacements. Comparison of the human gamma form with the corresponding isozyme from the rat shows only 7 replacements (compared to 27 changes between the human and rat alpha isozymes). We have identified regions of sequence difference between the human alpha and gamma forms that are mainly hydrophilic in character (residues 271-285, 298-316 and 416-433). These residues are on the surface of the three-dimensional structure and could be useful as immunogens to produce antibodies specific for the neurone-specific form.

Amino Acid Sequence↗