Aggregation of the histone h1 from the fruit fly Ceratitis capitata through disulphide bridges. Studies on their complexes with DNA

• 1.1. Three different major components, BG1, BG2 and BG3, have been obtained when the histone H1 from the fruit fly Ceratitis capitata is oxidized in vitro, separated by gel permeation chromatography and characterized by both amino acid analysis and polyacrylamide electrophoresis.
• 2.2. BG1 and BG2 correspond to the aggregation products by formation of intermolecular disulphide bridges, while BG3 is a monomeric component which shows the presence of one intramolecular disulphide bridge.
• 3.3. Structural studies by both circular dichroism and controlled tryptic digestion on BG1, BG2 and BG3 show the native conformation of H1 from the insect changes slightly and in a different range in each component.
• 4.4. All the subfractions induce PSI structure in DNA and stabilize the double helix of DNA, although quantitative differences appear.

     

Characterization of histones from plutei larvae of the sea urchin Tetrapygus niger

• 1.1. Histones were isolated from plutei larvae of the sea urchin Tetrapygus niger and analysed electrophoretically. Individual histones were purified and their amino acid compositions were determined.
• 2.2. The electrophoretic analysis revealed that larval histones are microheterogeneous; H1 exhibits four subforms, the nucleosomal core histones H2A, H2B and H3 were resolved into three subforms each and H4 had two subforms.
• 3.3. The comparisons of the amino acid compositions of plutei larvae histones with data from the literature of homonimus late variants isolated from gastrulas of other sea urchin species, indicate that late histone variants are conserved proteins with a very slight degree of species specificity and with general features of classical histones.

     

Relatedness of proteins estimated by amino acid composition and by tyrosine-containing tryptic peptides mapping: a case of apolipovitellins of Artemia salina (L.)

• 1.1. The structure of three apolipovitellin components of the brine shrimp, Artemia salina (L.), was analyzed by a sensitive peptide mapping technique using radioiodination.
• 2.2. The comparison of the tyrosine-containing tryptic peptides indicates that three apolipovitellins are structurally unrelated to one another.
• 3.3. However, a high degree of relatedness among three apolipovitellins is suggested by statistical treatment based on amino acid composition.

     

Modification of glyceraldehyde-3-phosphate dehydrogenase,EC 1.2.1.12, isolated from rainbow trout during acclimation at 5 or 15°C—II. Biochemical characterization of G3PDH muscle isolates

• 1.1. G3PDH was isolated from the lateral muscle of rainbow trout (Salmo gairdneri) acclimated at 5°C (cold) and 15°C (warm).
• 2.2. No differences were found in muscle concentration, molecular weights, isoelectric focusing patterns, amino acid compositions or peptide maps between cold and warm isolates.
• 3.3. Cold and warm G3PDH contained mannose in variable concentration but no other prosthetic groups.

     

Histone variants in diptera during metamorphosis

• 1.1. Patterns of histone variants from three diptera, Ceratitis capitata, Dacus oleae and Drosophila melanogaster were compared to mouse and to Plodia interpunctella variant patterns.
• 2.2. The three diptera contain histones which comigrate on two dimensional gels with H3.2, H3.3 and H4 in mouse and Plodia. H2A.1 and H2B.1 comigrate with Plodia H2A.1 and H2B.1 and are different from mouse, whilst H2A.Z has a different mobility to that of Plodia and mouse.
• 3.3. The iodinated peptides obtained from H2A.1 and H2A.2 of the diptera studied are compared to mouse and Plodia H2A.1 and H2A.Z peptides.
• 4.4. The histone variants from three developmental stages, larval, pupal and adult of the three diptera were identified and compared.
• 5.5. The same histone variant pattern is found through all stages of development.

     

Identification of the major annexins in Ehrlich ascites tumor cells

• 1.1. Three calcium-binding proteins have been purified from Ehrlich ascites tumor cells.
• 2.2. They were identified by amino acid sequence analysis on selected fragments obtained by tryptic digestion.
• 3.3. The proteins belong to the annexin family and were identified as annexins II, III and V.
• 4.4. Antibodies raised against the proteins were used to examine for their presence in a number of murine tissues.
• 5.5. The occurrence was found to be in reasonable accordance with earlier reports.

     

A comparative study of the basic nuclear proteins from sperm of bivalve molluscs

• 1.1. Basic nuclear proteins from spermatozoa of the three mollusc species belonging to the class Bivalvia have been analyzed using one- and two-dimensional electrophoresis.
• 2.2. Four nuclear basic proteins have been purified and their amino acid compositions determined.
• 3.3. In these spermatozoa histone-type proteins coexist with protamine-like proteins.
• 4.4. The protamine-like proteins that have been studied show different electrophoretic behavior but in general are similar, with a high content of lysine, arginine, alanine and serine.
• 5.5. Interspecific variability has been found for the H1-like histone.

     

Cloning and characterization of rabbit pancreatic colipase

• 1.1. Among the digestive enzymes synthesized by pancreas, lipase is the principle lipolytic enzyme which hydrolyses dietary glycerides.
• 2.2. For its action it requires a coenzyme, colipase.
• 3.3. The molecular mechanisms of the interaction of these two are not fully understood.
• 4.4. Further, molecular events that regulate and influence lipid absorption are ill denned.
• 5.5. The rabbit is the conventional animal model for the study of lipid absorption. We have undertaken the molecular cloning, and characterization of rabbit pancreatic colipase, the coenzyme for pancreatic lipase.
• 6.6. Colipase has been cloned from a gt 11 library of an adult rabbit pancreatic cDNA by probing with an oligonucleotide derived from human colipase sequence.
• 7.7. The total reading frame consists of 321 nucleotides coding for 90 amino acids of the functional protein and 17 nucleotides of the leader peptide.
• 8.8. Northern blot analysis revealed a distinct band around 0.5kb. Comparison with other species revealed an over all homology of 75% at the nucleotide level.
• 9.9. At the amino acid level highest conservation is observed at the lipase-binding region (AA 53–73).
• 10.10. Rabbit enzyme also retained the N-terminal pentapeptide of it preform.
• 11.11. The regions of homology and conservation may aid to define the sites of interaction of colipase with lipase.

     

Variability of histone H1 in rabbit populations

• 1.1. Perchloric acid-soluble proteins containing H1 histone as a main component were isolated from whole liver, lung and kidney of New Zealand White, Chinchilla, French Silver and Czech Spotted rabbits.
• 2.2. Proteins were resolved in a two-dimensional polyacrylamide slab gel into 4–5 spots depending on the tissue.
• 3.3. One of the histone subtypes, Hle, was found to be nonuniformly distributed within rabbit populations.
• 4.4. The prevailing fraction of animals had only a single spot of H1e (phenotype A). Approximately 10–28% of animals, depending on the breed, had two spots of H1e (e₁ and e₂; phenotype B) that slightly differed in the apparent molecular weights.
• 5.5. These two distinct gel patterns of H1e showed no tissue specificity, and the same phenotype was revealed in all tissues from the same animal.

     

The major dog pancreas protein recognized by an antiserum to dog prostate kallikrein is the anionic trypsin

• 1.1. On the basis of its immunoreactivity with a polyclonal antiserum to dog prostate kallikrein in Western blot experiments, a 30 kDa protein was purified from the pancreas of the dog using ion-exchange and gel filtration chromatography.
• 2.2. That protein was identified as the anionic trypsin by its NH₂-terminal amino acid sequence.
• 3.3. The immunoreaction occurred despite an overall amino acid homology which was limited to 39% between the prostate kallikrein and anionic trypsin.
• 4.4. Otherwise, the anti-prostatic kallikrein antiserum was rather specific since it did not react with dog cationic trypsin, dog renal kallikrein and human prostate specific antigen.

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Cotranslational fatty acylation of mucus glycoprotein. Addition of palmitic acid to peptidyl-tRNA occurs prior to peptide chain completion and its release

• 1.1. The fatty acylation of mucus glycoprotein nascent peptides was investigated using [³H]palmitic acid and [³⁵S]methionine-labeled peptidyl-tRNA of rat gastric mucous cells.
• 2.2. The mucus glycoprotein peptidyl-tRNA fraction was found to contain covalently bound palmitic acid in its complexes.
• 3.3. RNase digestion of the mucus glycoprotein peptidyl-tRNA released [³H]palmitic acid labeled peptides which, on SDS-polyacrylamide gel, separated into a multitude of bands ranging in size from 2000 to 60,000 Da.
• 4.4. The analyses of low molecular weight peptides revealed that palmitic acid was present in methionine-labeled peptides containing 30–43 amino acids and those of 18–25 amino acids or larger devoid of methionine, but was not identified in methionine-labeled peptides containing 10–15 amino acids.
• 5.5. The results indicate that the N-terminal fatty acylation of mucus glycoprotein nascent peptides is a cotranslational process which is occuring in an immediate vicinity of the signal peptide fragment.

     

Ostrich α-amylase: Purification and characterization of the pancreatic isoenzymes

• 1.1. Four ostrich pancreatic α-amylase isoenzymes were isolated by isoelectric focusing, following affinity chromatography on cyclohepta-amylose-Sepharose 4B.
• 2.2. Amino acid compositions of the four isoenzymes are very similar with only one charged amino acid (Arg) being significantly different.
• 3.3. The molecular weights, as determined by SDS-PAGE and amino acid composition, are nearly identical (52–53 kDa) for all four isoenzymes.
• 4.4. The four α-amylase isoenzymes appear to be kinetically distinct enzymes with a requirement for calcium.
• 5.5. Ostrich α-amylase isoenzymes appear to be non-glycosylated and contain one free thiol group.

     

Purification and characterization of the protamines and related proteins from the sperm of a tunicate,Styela plicata

• 1.1. We have characterized for the first time the major sperm-specific nuclear proteins (X, P1 and P2) of the tunicate Styela plicata. Both P1 and P2 have an amino acid composition that allows us to classify them as protamine-like proteins.
• 2.2. The protein P1 of lower electrophoretic mobility has a trypsin-resistant core which is compositionally related to that of histones of the H1 family and to the PL-I protein found in the sperm of marine invertebrates. The evolutionary significance of this finding is discussed.
• 3.3. In addition to P1 and P2, the sperm nucleus of S. plicata contains a protein X component which is also compositionally related to PL-I proteins from bivalve molluscs.
• 4.4. Besides these sperm-specific proteins, a full complement of somatic-like histones, including a somatic-like histone H1, is also present. These histones represent only a small fraction of the total nuclear proteins of the sperm.

     

Neurohypophysial hormones as molecular evolutionary tracers: investigations on the sturgeons Acipenser stellatus and Acipenser guldenstadti

• 1.1. Neurohypophysial hormones of two sturgeon species, Acipenser stellatus and Acipenser guldenstadti, have been purified through molecular sieving on Bio-Gel P4 and reverse-phase high pressure liquid chromatography on Nucleosil C18 columns.
• 2.2. Arginine vasotocin has been identified in both species by its retention time in partition chromatography, amino acid composition and, in the case of A. stellatus, by amino acid sequencing.
• 3.3. A second peptide has been purified and could be α-deamidated vasotocin.
• 4.4. Another peptide with oxytocic activity, distinct from the known oxytocin-like peptides, seems to be present in very small amounts.

     

A halogenated amino acid-containing sperm activating peptide and its related peptides isolated from the egg jelly of sea urchins,Tripneustes gratilla,Pseudoboletia maculata,Strongylocentrotus nudus,Echinometra mathaei and Heterocentrotus mammillatus

• 1.1. Twenty-eight peptides were isolated from the egg jelly of sea urchins, Tripneustes gratilla, Pseudoboletia maculata, Strongylocentrotus nudus, Echinometra mathaei (type A and B) and Heterocentrotus mammillatus and their amino acid sequences were determined.
• 2.2. Two of the peptides obtained from T. gratilla egg jelly possessed a bromophenylalanine (Br-Phe) residue in their sequences (Gly-(Br-Phe)-Asn-Leu-Asn-Gly-Gly-Gly-Val-Gly and Gly-(Br-Phe)-Asp-Leu-Asn-Gly-Gly-Gly-Val-Gly).
• 3.3. All of the peptides elevated cyclic GMP concentrations in the spermatozoa of the respective sea urchin and caused a shift in the apparent mol. wt of a major sperm protein of the respective sea urchin.
• 4.4. They stimulated respiration rates of the spermatozoa of Hemicentrotus pulcherrimus as well as their own species.
• 5.5. One-half maximal concentrations of the peptides for respiratory stimulation of H. pulcherrimus spermatozoa were between 10⁻¹¹ M and 10⁻⁹ M except a methionine-containing peptide which was about 10⁻⁷ M.

     

Isolation and characterization of glycosaminoglycans from atria of the human heart

• 1.1. Five glycosaminoglycans were isolated from tryptic digest of atria of the human heart and were assayed by determining the carbohydrate content of materials.
• 2.2. Separation of these 5 polymers was achieved by Dowex 1 × 2 column chromatography.
• 3.3. They were identified as hyaluronic acid, heparan sulfate, chondroitin-4-sulfate, dermatan sulfate and chondroitin-6-sulfate, respectively.

     

Amino acid composition and the protein form of procarboxypeptidase a purified from the pancreas of the sei whale Balaenoptera bolealis

• 1.1. Procarboxypeptidase (W-PCPA) was purified from the pancreas of the sei whale Balaenoptera bolealis.
• 2.2. W-PCPA was obtained as a homogeneous protein in polyacylamide gel disc electrophoresis.
• 3.3. W-PCPA has a molecular weight of 75,000.
• 4.4. Amino acid composition of W-PCPA was compared with that of bovine procarboxypeptidase as A S5 (PCPA-S5).
• 5.5. W-PCPA may be two subunits, and the aggregate form may resemble PCPA-S5.

     

Microheterogeneity of late histones in larval stages of sea urchin development

• 1.1. The total histone complement of early plutei were compared with that of intermediate and late larvae of the sea urchin Tetrapygus niger.
• 2.2. Electrophoretic comparison indicates that there are quantitative and qualitative shifts of the five classes throughout late larval development.
• 3.3. The strong similarity in the amino acid composition of total histones isolated from early, intermediate and late plutei indicates that the observed electrophoretic heterogeneity is due to post-translational modifications.

     

Hydrolysis of proteins by peptide hydrolases of Antarctic krill,Euphausia superba

• 1.1. The hydrolysis of casein by peptide hydrolases of Antarctic krill, E. superba, has been
• 2.2. The peptide hydrolases studied included trypsin-like enzymes, carboxypeptidase A-type of enzymes, carboxypeptidase B-type of enzymes, and an aminopeptidase isolated from Antarctic krill.
• 3.3. The trypsin-like enzymes seemed to play a decisive role in the degradation of casein, whereas the carboxypeptidase A, carboxypeptidase B and the aminopeptidase had limited effect when acting on casein alone. When combined with the trypsin-like enzymes, the exopeptidases effected enhanced release of amino acids from the protein.
• 4.4. Based on the pattern of amino acids relased from casein by a crude extract of krill, and by the isolated peptide hydrolases either alone or in combination, it is concluded that the purified peptide hydrolases examined comprise the major enzymes responsible for the autoproteolytic activity of krill at neutral- to weakly alkaline pH.