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1.
J Oral Rehabil ; 44(3): 205-212, 2017 Mar.
Article in English | MEDLINE | ID: mdl-27997984

ABSTRACT

Dental arch morphology and tooth position are affected by lip-closing force (LCF). This study aimed to quantitatively evaluate the relationships between the horizontal or vertical balance of the LCF generated during maximum voluntary pursing-like movements and dental arch length (DAL) or width (DAW) or the lingual inclination of the upper or lower 1st molars (LIUM, LILM) in patients with Angle Class I malocclusion. Sixteen subjects with Angle Class I malocclusion (median age: 23·4 ± 5·9 years) who had never undergone orthodontic treatment were randomly selected. LCF was measured in eight directions during maximum voluntary pursing-like lip-closing movements. Dental arch models were scanned and analysed to obtain DAW, DAL, LIUM and LILM measurements. Mandibular deviation was measured on posteroanterior cephalograms. A significant negative correlation was detected between maxillary DAL and upper LCF. Maxillary DAL, DAW and the DAL/DAW ratio displayed significant negative correlations with total LCF and upper LCF. However, no significant correlations were detected between any mandibular dental arch morphological parameter and LCF. The difference in the LIUM between the deviation and non-deviation sides exhibited a significant positive correlation with the difference in upper LCF between the deviation and non-deviation sides and was significantly negatively correlated with the difference in lower LCF between the deviation and non-deviation sides. These results suggest that upper LCF is related to maxillary DAL, and the horizontal balance of the LCF of the upper and lower lips is related to the LIUM during pursing-like lip-closing movements in patients with Angle Class I malocclusion.


Subject(s)
Dental Arch/pathology , Facial Muscles/physiopathology , Lip/physiopathology , Malocclusion, Angle Class I/physiopathology , Cephalometry , Dental Arch/physiopathology , Female , Humans , Male , Models, Dental , Skull , Young Adult
2.
Euro Surveill ; 18(15): 20453, 2013 Apr 11.
Article in English | MEDLINE | ID: mdl-23594575

ABSTRACT

Novel influenza viruses of the H7N9 subtype have infected 33 and killed nine people in China as of 10 April 2013. Their haemagglutinin (HA) and neuraminidase genes probably originated from Eurasian avian influenza viruses; the remaining genes are closely related to avian H9N2 influenza viruses. Several characteristic amino acid changes in HA and the PB2 RNA polymerase subunit probably facilitate binding to human-type receptors and efficient replication in mammals, respectively, highlighting the pandemic potential of the novel viruses.


Subject(s)
Influenza A Virus, H9N2 Subtype/isolation & purification , Influenza in Birds/diagnosis , Orthomyxoviridae Infections/transmission , Animals , Birds , Female , Humans , Influenza A Virus, H9N2 Subtype/pathogenicity , Influenza, Human/diagnosis , Male
3.
Rev Sci Instrum ; 86(5): 056103, 2015 May.
Article in English | MEDLINE | ID: mdl-26026564

ABSTRACT

A CR-39 plastic nuclear track detector was used for quality assurance of mixed oxide fuel pellets for next-generation nuclear power plants. Plutonium (Pu) spot sizes and concentrations in the pellets are significant parameters for safe use in the plants. We developed an automatic Pu detection system based on dense α-radiation tracks in the CR-39 detectors. This system would greatly improve image processing time and measurement accuracy, and will be a powerful tool for rapid pellet quality assurance screening.

4.
J Clin Endocrinol Metab ; 85(2): 743-7, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10690885

ABSTRACT

Hypophosphatasia is characterized by the hypomineralization of bone associated with the mutation of the tissue-nonspecific alkaline phosphatase (TNSALP) gene. Although the disease is usually autosomal recessive, an autosomal dominant form is also recognized. Approximately 50 mutations have been found in the TNSALP gene in patients with hypophosphatasia. However, the mutations identified to date do not seem to account for the dominantly inherited form of the disease. We have examined a German family in which the father and all 4 children were affected with hypophosphatasia, whereas the mother was healthy. The affected members of this family showed premature loss of deciduous teeth at or shortly before 2 yr of age and low levels of serum ALP with elevated levels of urinary phosphoethanolamine. DNA analysis by direct sequencing revealed a heterozygous missense mutation that caused the conversion of amino acid Asp to Val at position 361 (D361V) in the patients. Another substitution was detected in exon 12 (Val to Ala conversion at codon 505: V505A) in 1 allele of the mother and 3 children, indicating no association of the substitution with the disease. Reconstruction experiments demonstrated that the D361V mutant protein lost its enzymatic activity and that it inhibited the function of wild-type enzyme when coexpressed in COS-7 cells. On the other hand, the V505A mutant exhibited enzymatic activities equal to those of the wild-type ALP. It is likely that the mutant D361V protein forms dimers with the wild-type protein, and the protein-protein interaction contributes to the dominant effect of the mutant D361V. The mutation that causes D361V is the first one proven to be associated with the dominant form of hypophosphatasia.


Subject(s)
Alkaline Phosphatase/genetics , Alkaline Phosphatase/metabolism , Genes, Dominant , Hypophosphatasia/enzymology , Hypophosphatasia/genetics , Mutation/genetics , Adult , Amino Acid Sequence/genetics , Child , DNA Mutational Analysis , DNA, Complementary/genetics , Female , Gene Expression , Humans , Isoenzymes/genetics , Isoenzymes/metabolism , Male , Pedigree
5.
FEBS Lett ; 448(2-3): 257-60, 1999 Apr 09.
Article in English | MEDLINE | ID: mdl-10218487

ABSTRACT

A cDNA clone for an inhibitor of Bombyx cysteine proteinase was isolated and sequenced. Active inhibitor proteins were expressed in Escherichia coli using the cDNA. The open reading frame of the cDNA encodes a 105 residues protein with 19 residues of a signal sequence. The inhibitor has amino acid sequences homologous to several cysteine proteinases, but only to their propeptide sequences. The results suggest that some cysteine proteinase proregions may have evolved as autonomous modules and become inhibitor proteins for cysteine proteinases.


Subject(s)
Bombyx/enzymology , Cysteine Endopeptidases/chemistry , Cysteine Proteinase Inhibitors/genetics , Amino Acid Sequence , Animals , Base Sequence , Blotting, Northern , Cloning, Molecular , Databases, Factual , Electrophoresis, Polyacrylamide Gel , Escherichia coli/genetics , Models, Genetic , Molecular Sequence Data , Sequence Homology, Amino Acid
6.
Bone ; 30(2): 436-9, 2002 Feb.
Article in English | MEDLINE | ID: mdl-11856654

ABSTRACT

A case of infantile malignant osteopetrosis is described. The patient died from respiratory hemorrhage at 7 months of age despite treatment that included high doses of active vitamin D and administration of interferon-gamma. A postmortem examination revealed the presence of many osteoclasts in the bone, which lacked ruffled borders. This observation was consistent with the histology of bone reported in Atp6i-knockout mice, which lack the gene encoding the a3 subunit of vacuolar-type H(+)-adenosine triphosphatase (ATPase). Sequence analysis of the TCIRG1 gene encoding the a3 subunit revealed two novel mutations: a deletion/insertion mutation in exon 9 and a T-to-C transition at the splice donor site of intron 19. The former mutation caused a frame shift and premature stop codon. The latter was associated with abnormal splicing, which was confirmed by sequencing the products amplified by reverse transcription-polymerase chain reaction (RT-PCR), using total RNA from the liver specimen as template. Although several mutations in the TCIRG1 gene in infantile malignant osteopetrosis have been reported in other populations, this is the first case of a Japanese patient with a mutation identified in this gene. These results support the important role of the subunit in the function of the proton pump.


Subject(s)
Frameshift Mutation , Gene Deletion , Osteopetrosis/genetics , Vacuolar Proton-Translocating ATPases/genetics , Codon, Terminator/genetics , Exons , Fatal Outcome , Female , Humans , Infant, Newborn , Introns , Japan , Osteoclasts/pathology , Osteopetrosis/pathology , RNA Splice Sites/genetics , Vacuolar Proton-Translocating ATPases/chemistry
7.
Virus Res ; 73(1): 67-79, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11163645

ABSTRACT

The 5' noncoding region (NCR) of hepatitis C virus (HCV) contains an internal ribosome entry site for translation initiation. Cellular proteins (e.g. La, polypyrimidine tract-binding protein, and p25) that interact with HCV 5' NCR have been implicated in facilitating efficient internal initiation. The 5' NCR may also contain RNA structures and specific RNA sequences that interact with cellular proteins to promote RNA replication. UV crosslinking experiments revealed a 43-kDa cellular protein (p43) also interacts with the HCV 5' NCR. Further UV crosslinking experiments with deletion mutants of HCV 5' NCR demonstrated that p43 bound specifically to the 5'-terminal stem-loop of the HCV 5' NCR. Achromobactor proteinase I digests, competition experiments, and immunoprecipitation confirmed that p43 was identical to human poly(rC)-binding protein 2 (PCBP2). We prepared a PCBP2-immunodepleted rabbit reticulocyte lysate with an anti-PCBP2 antibody. Translation activity promoted by the HCV internal ribosome-entry site was the same in PCBP2-depleted lysates as in mock-depleted lysates. In conclusion, PCBP2 specifically interacted with the 5' terminus of HCV genome but had no effect on HCV translation. We speculate that PCBP2's interaction with HCV 5' NCR may be involved in the replication-initiation complex of HCV.


Subject(s)
5' Untranslated Regions/metabolism , DNA-Binding Proteins , Genome, Viral , Hepacivirus/metabolism , Heterogeneous-Nuclear Ribonucleoproteins , RNA-Binding Proteins/metabolism , Transcription Factors , 5' Untranslated Regions/chemistry , Binding Sites , Cell Extracts , Gene Deletion , HeLa Cells , Hepacivirus/genetics , Humans , Mutation , Nucleic Acid Conformation , Protein Binding , Protein Biosynthesis , RNA, Viral/metabolism , RNA-Binding Proteins/analysis , Ultraviolet Rays , Virus Replication
8.
Sleep ; 20(11): 963-71, 1997 Nov.
Article in English | MEDLINE | ID: mdl-9456461

ABSTRACT

In an effort to identify risk factors for insomnia and determine the contribution of nightime road traffic volume to insomnia in the general population, a questionnaire survey was carried out among 3,600 adult Japanese women living in eight urban residential areas. The crude prevalence rate of insomnia was 11.2%. Multivariate analysis revealed that aging, living with a child/children aged six or younger, undergoing medical treatment, experiencing major life events, having an irregular bedtime, having a sleep apnealike symptom, and living near a road with a heavy volume of traffic are risk factors for insomnia. Taking into account other risk factors, there was a level-response relationship between the nighttime traffic volume of main roads and the risk of insomnia in the subjects living in the zones 0-20 m from these roads. These results suggest that road traffic noise raises the sound level in bedrooms in such zones, and consequently the prevalence rate of insomnia among the residents, and that noise-induced insomnia is an important public health problem, at least in highly urbanized areas. To confirm this, a further study on noise exposure is needed.


Subject(s)
Automobile Driving , Sleep Initiation and Maintenance Disorders/etiology , Adult , Aged , Aging/physiology , Female , Humans , Japan/epidemiology , Middle Aged , Noise/adverse effects , Psychiatric Status Rating Scales , Risk Factors , Sleep Initiation and Maintenance Disorders/diagnosis , Sleep Initiation and Maintenance Disorders/epidemiology , Surveys and Questionnaires , Urban Population/statistics & numerical data , Wakefulness
9.
Am J Med Genet ; 88(5): 560-6, 1999 Oct 15.
Article in English | MEDLINE | ID: mdl-10490717

ABSTRACT

We investigated the retroviral/retroposon hypothesis of schizophrenia by generating sequences with PCR primers based on a retroviral sequence recovered by Yee et al. [1998: Schizophr Res 29:92] from a cDNA library from postmortem brain tissue from an individual with psychosis in a genomic region (Xq21.3) that has been tentatively linked to schizophrenia and schizoaffective disorder by Laval et al. [1998: Am. J. Med. Genet. (Neuropsychiatr. Genet.) 81:420-427]. Within the block of homology with Yp that was generated by a transposition between the chimpanzee and Homo sapiens we find two sequences, HS307 and HS408, with a high degree of homology to but not identity with the schizophrenic brain cDNA. The closest match of these three sequences is to a family of retroposons, that has evolved from the HERV-K family of endogenous retroviruses, some members of which (e.g., SINE-R.C2) appear to be specific to the human genome. This element has been reported as a cause of Fukuyama-type muscular dystrophy [Kobayashi et al., 1998: Nature 394:388-392]. Such retroposons, as agents of change in the human genome, provide a strategy for investigating pathogenesis. On account of their genomic location in a region that has been subject to change in the course of hominid evolution, and that may have a relationship to psychosis and/or cerebral asymmetry, we conclude that these particular insertions deserve further investigation.


Subject(s)
Brain/metabolism , Complement C2/genetics , Functional Laterality/genetics , Psychotic Disorders/genetics , Retroelements/genetics , Schizophrenia/genetics , X Chromosome , Y Chromosome , Animals , Base Sequence , DNA, Complementary/genetics , Endogenous Retroviruses/genetics , Evolution, Molecular , Genetic Predisposition to Disease , Haplorhini , Humans , Models, Genetic , Molecular Sequence Data , Phylogeny , Sequence Homology, Nucleic Acid
10.
Antiviral Res ; 27(1-2): 19-37, 1995 May.
Article in English | MEDLINE | ID: mdl-7486956

ABSTRACT

Traditional herbal medicines have been safely used for the treatment of various human diseases since ancient China. We selected 10 herbal extracts with therapeutic antiherpes simplex virus type 1 (HSV-1) activity. Among these, Geum japonicum Thunb., Rhus javanica L., Syzygium aromaticum (L.) Merr. et Perry, or Terminalia chebula Retzus showed a stronger anti-HSV-1 activity in combination with acyclovir than the other herbal extracts in vitro. When acyclovir and/or a herbal extract were orally administered at doses corresponding to human use, each of the 4 combinations significantly limited the development of skin lesions and/or prolonged the mean survival times of infected mice compared with both acyclovir and the herbal extract alone (P < 0.01 or 0.05). These combinations were not toxic to mice. They reduced virus yields in the brain and skin more strongly than acyclovir alone and exhibited stronger anti-HSV-1 activity in the brain than in the skin, in contrast to acyclovir treatment by itself. Combinations of acyclovir with historically used herbal medicines showed strong combined therapeutic anti-HSV-1 activity in mice, especially reduction of virus yield in the brain.


Subject(s)
Acyclovir/therapeutic use , Drugs, Chinese Herbal/therapeutic use , Herpes Simplex/drug therapy , Herpesvirus 1, Human/drug effects , Acyclovir/toxicity , Animals , Chlorocebus aethiops , Drug Therapy, Combination , Drugs, Chinese Herbal/toxicity , Female , Herpesvirus 1, Human/growth & development , Humans , Mice , Mice, Inbred BALB C , Vero Cells , Viral Plaque Assay
11.
J Biochem ; 127(5): 761-70, 2000 May.
Article in English | MEDLINE | ID: mdl-10788784

ABSTRACT

Pepsinogens A and C, and prochymosin were purified from four species of adult New World monkeys, namely, common marmoset (Callithrix jacchus), cotton-top tamarin (Saguinus oedipus), squirrel monkey (Saimiri sciureus), and capuchin monkey (Cebus apella). The occurrence of prochymosin was quite unique since this zymogen is known to be neonate-specific and, in primates, it has been thought that the prochymosin gene is not functional. No multiple form has been detected for any type of pepsinogen except that two pepsinogen-A isozymogens were identified in capuchin monkey. Pepsins A and C, and chymosin hydrolyzed hemoglobin optimally at pH 2-2.5 with maximal activities of about 20, 30, and 15 units/mg protein. Pepsins A were inhibited in the presence of an equimolar amount of pepstatin, and chymosins and pepsins C needed 5- and 100-fold molar excesses of pepstatin for complete inhibition, respectively. Hydrolysis of insulin B chain occurred first at the Leu15-Tyr16 bond in the case of pepsins A and chymosins, and at either the Leu15-Tyr16 or Tyr16-Leu17 bond in the case of pepsins C. The presence of different types of pepsins might be advantageous to New World monkeys for the efficient digestion of a variety of foods. Molecular cloning of cDNAs for three types of pepsinogens from common marmoset was achieved. A phylogenetic tree of pepsinogens based on the nucleotide sequence showed that common marmoset diverged from the ancestral primate about 40 million years ago.


Subject(s)
Cebidae/genetics , Chymosin/genetics , Enzyme Precursors/genetics , Evolution, Molecular , Pepsinogen A/genetics , Pepsinogen C/genetics , Amino Acid Sequence , Animals , Base Sequence , Chymosin/antagonists & inhibitors , Cloning, Molecular , DNA, Complementary/genetics , Enzyme Precursors/antagonists & inhibitors , Likelihood Functions , Molecular Sequence Data , Pepsinogen A/antagonists & inhibitors , Pepsinogen A/chemistry , Pepsinogen C/antagonists & inhibitors , Pepsinogen C/chemistry , Sequence Homology, Amino Acid , Substrate Specificity , Vertebrates/genetics
12.
J Biochem ; 97(4): 1235-46, 1985 Apr.
Article in English | MEDLINE | ID: mdl-3928607

ABSTRACT

Japanese monkey progastricsin was shown to be activated to gastricsin exclusively by a two-step process through an intermediate form. The occurrence of this process was substantiated by the isolation of the intermediate form and released peptides. By NH2-terminal sequence analyses of these protein and peptide species, the amino acid sequence of the 43-residue activation segment (propart) was determined to be as follows: (Formula: see text) The NH2-terminal 26-residue peptide was released first, resulting in generation of the intermediate form. The subsequent release of peptides, residues Nos. 27-40 and 27-43, generated two gastricsins as the final products. This two-step process of activation of Japanese monkey progastricsin is in striking contrast to the one-step activation process occurring exclusively for pepsinogen A of the same monkey species. The course of molecular evolution of pepsinogens including progastricsins was deduced from the amino acid sequences of their activation segments by constructing phylogenic trees. The trees divided pepsinogens into 3 clusters, i.e., pepsinogens A, progastricsins and prochymosin, showing that these three groups diverged from one another very early on in the course of the evolution of pepsinogens.


Subject(s)
Enzyme Precursors/metabolism , Pepsin A/metabolism , Pepsinogens/genetics , Amino Acid Sequence , Animals , Biological Evolution , Enzyme Activation , Humans , Macaca/physiology , Molecular Weight , Mutation , Species Specificity
13.
J Biochem ; 84(4): 771-8, 1978 Oct.
Article in English | MEDLINE | ID: mdl-101535

ABSTRACT

Purified Japanese monkey pepsinogens I and II contain carbohydrate as a part of the enzyme molecule. By gel filtration on Sephadex G-100, chromatography on DE-32 cellulose, and polyacrylamide disc gel electrophoresis, the carbohydrate moiety could not be separated from the enzyme protein, and the content did not decrease on repeated chromatography. Glycopeptides were obtained by successive digestion of pepsinogens with thermolysin and aminopeptidases and isolated by chromatography on Sephadex G-25 and G-50. Identification and determination of carbohydrate components was performed by paper and gas-liquid chromatographies. The presence of 4 glucosamines, 6 galactoses, 6--8 mannoses, and 8--11 fucoses per molecule of the glycopeptide of both pepsinogens was observed, of which the high content of fucose is especially unique. The molecular weight of the carbohydrate chains should be around 4,000--5,000. The amino acid sequence of a major glycopeptide was deduced to be Ile-Gly-Ile-Gly-Thr-Pro-Gln-Ala-Asn, in which the asparagine residue is the site of attachment of the carbohydrate chain.


Subject(s)
Pepsin A , Pepsinogens , Amino Acid Sequence , Amino Acids/analysis , Animals , Carbohydrates/analysis , Glycopeptides/analysis , Haplorhini , Peptide Fragments/analysis , Protein Binding
14.
J Biochem ; 79(3): 455-68, 1976 Mar.
Article in English | MEDLINE | ID: mdl-820694

ABSTRACT

Five pepsinogens were purified from gastric mucosa of Japanese monkey by DEAE-cellulose column chromatography and Sephadex G-100 gel filtration. Each was shown to be homogeneous by polyacrylamide disc gel electrophoresis. They were designated as pepsinogens I, II, III-1, III-2, and III-3, respectively, based on the elution profile on DEAE-cellulose chromatography. The molecular weights of pepsinogens I and II were 48,000 and 43,000, respectively, and those of the other three were 40,000. Each pepsinogen was converted to pepsin [EC 3.4.23.1] by acidification, and some characteristics, e.g. the pH dependence of activity, sensitivity to various inhibitors, stability to alkali, and hydrolytic activity toward N-acetyl-L-phenylalanyl-3,5-diiodo-L-tyrosine (APDT), were determined. The characteristics of pepsins I and II were the same, and those of pepsins III-1, III-2, and III-3 were similar. Pepsin III-3 showed high stability to alkali (pH 8.0), while the others were less stable. Each pepsin hydrolyzed APDT and was inhibited by acid protease-specific inhibitors, e.g. pepstain, diazoacetyl-DL-norleucine methyl ester (DAN), 1,2-epoxy-3-(p-nitrophenoxy)propane (EPNP), and p-bromophenacyl bromide. The compositions of pepsins I and II were the same, indicating that they are the same protein, and those of pepsins III-1, III-2, and III-3 resembled that of human pepsin. The diversity of pepsinogens and pepsins is discussed in comparison with pepsinogens and pepsins from other animals.


Subject(s)
Gastric Mucosa/enzymology , Pepsin A/metabolism , Pepsinogens/metabolism , Amino Acids/analysis , Animals , Female , Haplorhini , Macaca , Male , Molecular Weight , Pepsinogens/isolation & purification , Pepstatins/pharmacology , Protein Denaturation
15.
J Biochem ; 92(4): 1179-88, 1982 Oct.
Article in English | MEDLINE | ID: mdl-6816791

ABSTRACT

When Japanese monkey pepsinogen was activated at pH 2.0 in the absence of pepstatin, the activation segment of the amino(N)-terminal 47 residues was released as a single intact polypeptide. This clearly shows that the pepsinogen was activated to pepsin directly. This direct activation was called a 'one-step' process. On the other hand, when pepsinogen was activated at pH 2.0 in the presence of pepstatin, an appreciable amount of pepsinogen was converted to an intermediate form between pepsinogen and pepsin, although a part of pepsinogen was activated directly to pepsin. The intermediate form was generated by releasing the N-terminal 25 residues of pepsinogen. This activation through the intermediate form is thought to be a 'two-step' or 'stepwise-activating' process involving a bimolecular reaction between pepstatin-bound pepsinogen and free pepsin.


Subject(s)
Pepsin A/biosynthesis , Pepsinogens/metabolism , Animals , Chemical Phenomena , Chemistry , Enzyme Activation/drug effects , Hydrogen-Ion Concentration , Macaca , Pepstatins/pharmacology , Spectrophotometry, Ultraviolet
16.
J Biochem ; 88(1): 9-16, 1980 Jul.
Article in English | MEDLINE | ID: mdl-6773933

ABSTRACT

The complete amino acid sequence of the activation peptide segment of the major component of Japanese monkey pepsinogens was determined. The pepsinogen was converted to pepsin by incubation at pH 2.0 and 14 degrees C for 17 min. The activation peptides were separated from the resulting pepsin and purified by chromatography on columns of sulfopropyl (SP)-Sephadex. One 25-residue peptide and two 22-residue peptides were isolated and their amino acid sequences were determined. The results showed that the former peptide was derived from the amino-terminal half (residues no. 1 to 25) and the latter peptides from the carboxyl-terminal half (residues no. 26 to 47) of the activation segment. The latter two peptides were identical except for a single amino acid replacement. The complete amino acid sequence of the whole activation peptide segment was thus deduced as follows: Ile1-Ile-Tyr-Lys-Val-Pro-Leu-Val-Arg-Lys10-Lys-Ser-Leu-Arg-Arg-Asn-Leu-Ser-Glu- His20-Gly-Leu-Leu-Lys-Asp-Phe-Leu-Lys-Lys-His30-Asn-Leu-Asn-Pro-Ala-Ser-Lys-Tyr -Phe-Pro40-LysGln-Ala-Glu-Ala-Pro-Thr-Leu47. The whole chain was composed of 47 residues, and cleaved into two polypeptides by the cleavage of Asp25-Phe26 bond during activation. Two amino acids were detected at residue-41, i.e., glutamine and lysine, indicating the presence of two closely related pepsinogens in the sample used. The total number of residues (47) of the whole activation peptide segment is 3 and 2 residues larger than those of porcine pepsinogen and bovine pepsinogen, respectively. The differences are 15 and 22 residues as compared with porcine pepsinogen and bovine pepsignogen, respectively.


Subject(s)
Pepsin A/metabolism , Pepsinogens/metabolism , Amino Acid Sequence , Animals , Cattle , Chemical Phenomena , Chemistry , Enzyme Activation , Kinetics , Macaca , Peptide Fragments/analysis , Species Specificity , Swine
17.
J Biochem ; 88(2): 571-82, 1980 Aug.
Article in English | MEDLINE | ID: mdl-6774973

ABSTRACT

Upon activation of human pepsinogen A at pH 2.0 in the presence of pepstatin, an intermediate form was generated together with pepsin A. This activation intermediate could be separated from pepsinogen A and pepsin A by DE-32 cellulose chromatography at pH 5.5. It had a molecular weight intermediate between those of pepsinogen A and pepsin A, and contained about half the number of basic amino acid residues in pepsinogen A. It had phenylalanine as the amino(N)-terminal amino acid, and was deduced to be generated by release of N-terminal 25 residue segment from pepsinogen A. Amino acid sequence determination of the N-terminal portions of pepsinogen A and the intermediate from enabled us to elucidate the entire acid sequence of the 47-residue activation peptide segment as follow: [Formula: see text]. On the other hand, upon activation of pepsinogen A at pH 2.0 in the absence of pepstatin, cleavage of the activation segment occurred at several additional bonds. In addition, upon activation both in the presence and in the absence of pepsitatin, an additional activation intermediate, designated pepsin A', was formed in minor quantities. This form was identical with pepsin A, except that it had an additional Pro-Thr-Leu sequence preceding the N-terminal valine of pepsin A.


Subject(s)
Pepsinogens/metabolism , Amino Acid Sequence , Amino Acids/analysis , Animals , Cattle , Enzyme Activation , Gastric Mucosa/enzymology , Haplorhini , Humans , Kinetics , Pepsin A , Pepsinogens/isolation & purification , Pepstatins/pharmacology , Peptide Fragments/isolation & purification , Species Specificity , Swine
18.
J Biochem ; 88(3): 635-45, 1980 Sep.
Article in English | MEDLINE | ID: mdl-6774974

ABSTRACT

Pepsinogens were purified from the gastric mucosa of the crab-eating monkey, Macaca fascicularis. Eight pepsinogens were shown to be present disc-electrophoretically and they were termed pepsinogens I-a, I-b, III-1-a, III-1-b, III-2-a, III-2-b, III-3, and C, based on the nomenclature used for Japanese monkey pepsinogens. The molecular weights were 43,000 for pepsinogens I-a and I-b, 40,000 for pepsinogens III-1-a, III-1-b, III-2-a, III-2-b, and III-3, and 38,000 for pepsinogen C, as determined by sodium dodecyl sulfate-polyacrylamide disc gel electrophoresis. Pepsinogens I-a and I-b contained carbohydrate amounting to about 4-5% by weight. Each was activated to pepsin by acidification at pH 2.0. Pepsinogen III-1 (a mixture of III-1-a and III-1-b) yielded a single pepsin, i.e. pepsin III-1, and pepsinogen III-2 (a mixture of III-2-a and III-2-b) also gave a single pepsin, i.e. pepsin III-2. The molecular weights were estimated to be 38,000 for pepsins I-a and I-b, 35,000 for pepsins III-1, III-2, and III-3, and 34,000 for pepsin C. Optimal pHs toward acid-denatured hemoglobin were 1.9, 2.3, 2.0, 2.0, and 2.3 for pepsins I-a, III-1, III-2, III-3, and C, respectively. Pepstatin, diazoacetyl-DL-norleucine methyl ester (DAN), 1,2-epoxy-3-(p-nitrophenoxy)propane (EPNP), and p-bromophenacyl bromide inhibited each pepsin. Amino acid compositions of the pepsinogens and pepsins were determined. Pepsinogen C and pepsin C were distinct from the other pepsinogens and pepsins in their high ratios of glutamic acid to aspartic acid, and leucine to isoleucine. Amino acid sequences of the amino (N)-terminal 14 residues of pepsinogens were determined by the manual Edman procedure. One to three substitutions of amino acids were observed in the 14-residue segments among the pepsinogens except for pepsinogen C. There were 7 amino acid substitutions between pepsinogens C and III-3. These results suggest that the amino acid substitutions in the N-terminal region contribute considerably to the heterogeneity of pepsinogens.


Subject(s)
Gastric Mucosa/enzymology , Pepsin A/metabolism , Pepsinogens/metabolism , Amino Acid Sequence , Animals , Hydrogen-Ion Concentration , Macaca fascicularis , Molecular Weight , Pepsinogens/isolation & purification
19.
J Biochem ; 87(3): 725-35, 1980 Mar.
Article in English | MEDLINE | ID: mdl-6993448

ABSTRACT

A cathepsin D-like acid proteinase from human gastric mucosa was purified for the first time to homogeneity as examined by polyacrylamide disc gel electrophoresis. The molecular weight of the enzyme was estimated to be about 85,000 by gel filtration on Sephadex G-150 and, after treatment with 2-mercaptoethanol, about 38,000 by sodium dodecyl sulfate-polyacrylamide disc gel electrophoresis. These results indicate that the native enzyme is composed of two apparently identical monomeric units. The protein band could also be stained with the Schiff reagent after periodate oxidation, indicating that the proteinase is a glycoprotein. Analyses showed that the enzyme contains approximately 4 glucosamine and 16 mannose residues per molecule (M.W. 85,000). The amino acid composition generally resembled those of cathepsins D except for the lower contents of basic amino acid residues, especially lysine. It also showed some similarity to pepsinogens. The optimal pH was 2.3--3.5 with hemoglobin as a substrate. The enzyme was strongly inhibited, like pepsin, by 1,2-epoxy-3-(p-nitrophenoxy)propane (EPNP) as well as by pepstatin and diazoacetyl-DL-norleucine methyl ester (DAN) in the presence of cupric ions. The proteinase was stable in alkaline solution up to pH 9.0, and was rather stable to sequential acidification and neutralization. The acidification resulted in an increase of electrophoretic mobility towards the anode.


Subject(s)
Cathepsins/isolation & purification , Endopeptidases/isolation & purification , Gastric Mucosa/enzymology , Amino Acids/analysis , Carbohydrates/analysis , Chemical Phenomena , Chemistry , Electrophoresis, Polyacrylamide Gel , Humans , Molecular Weight
20.
J Biochem ; 93(3): 743-54, 1983 Mar.
Article in English | MEDLINE | ID: mdl-6409894

ABSTRACT

Activation of porcine pepsinogen at pH 2.0 was found to proceed simultaneously by two different pathways. One pathway is the direct conversion process of pepsinogen to pepsin, releasing the intact activation segment. The isolation of the released 44-residue segment was direct evidence of this one-step process. At pH 5.5 the segment bound tightly to pepsin to form a 1:1 pepsin-activation segment complex, which was chromatographically indistinguishable from pepsinogen. The other is a stepwise-activating or sequential pathway, in which pepsinogen is activated to pepsin through intermediate forms, releasing activation peptides stepwisely. These intermediate forms were isolated and characterized. The major intermediate form was shown to be generated by removal of the amino-terminal 16 residues from pepsinogen. The released peptide mixture was composed of two major peptides comprising residues 1-16 and 17-44, and hence the stepwise-activating process was deduced to be mainly a two-step process.


Subject(s)
Pepsin A/biosynthesis , Pepsinogens/metabolism , Amino Acids/analysis , Animals , Chemical Phenomena , Chemistry , Enzyme Activation , Peptide Fragments/isolation & purification , Swine
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