Hemolymph iron in Crustacea decapoda during the intermolt cycle

A study on the iron content in the hemolymph of Austropotamobius pallipes and Carcinus maenas has been made. The hemolymph iron content and the total iron binding capacity were investigated in males and females of both species. The values obtained for hemolymph iron content in the males were between 154 and 430 mug/100/ml and in the females between 134 and 431 mug/100/ml. The total iron binding capacity for the males was between 472 and 762 mug/100/ml and for the females between 390 and 698 mug/100/ml. The variations occurring in both parameters during different stages of the intermolt were also studied. The first increase in hemolymph iron coincides with the postmolt stage. During the intermolt, the need for iron decreases as the rate of tissue synthesis becomes lower. Finally an enormous increase in the hemolymph iron content was observed during the molt.

Haemocyanins in spiders, III. Chemical and physical properties of the proteins in Dugesiella and Cupiennius blood

The haemolymph of the tarantulas, Dugesiella (Eurypelma) californica and Dugesiella (Eurypelma) helluo contains high molecular weight haemocyanin (80-82% of total blood proteins) and a second protein not related to haemocyanin (18-20%). In the Lycosid spider, Cupiennius salei, haemocyanin (75% of total blood protein) occurs in two states of association. The haemocyanins were isolated by ultracentrifugation, gel filtration, isoelectric focusing, or preparative gel electrophoresis. Their sedimentation constants are 36.7 S (both tarantulas), 23.4 S and 15.9 S (Cupiennius). After alkaline dissociation, polypeptides sedimenting at 5.8 S (D. californica) and 4.7 S (Cupiennius) were obtained. The molecular weight of the intact functional subunit is (by sedimentation equilibrium) 70 300 (D. californica) and 69 900 (Cupiennius). Copper analysis results in closely similar values. By sodium dodecylsulphate gel electrophoresis, molecular weights of 71 000 (D. californica), 72 000 (Cupiennius) and 74 000 (D. helluo) were obtained. Denaturation with various agents did not lead to smaller polypeptides. The amino acid composition of the haemocyanins was determined (Table 1). The amino end group is blocked. The haemocyanins contain 1.2-1.5% of neutral carbohydrates and 0.3-0.5% of glucosamine (possibly acetylated). The neutral carbohydrates were identified with glucose, mannose, fucose, and arabinose, glucose being the dominant species. Neuraminic acid was not detected. The haemocyanins of the three species cannot be distinguished by their carbohydrate moieties, while there is a significant difference in amino acid composition between tarantula and Cupiennius haemocyanins. The second, non-respiratory protein isolated from spider blood sediments with 16.1 S (Dugesiella) or 15.9 S (Cupiennius). Its isoelectric point is at pH 5.5 It is stable in weakly alkaline solutions but can be denatured to yield polypeptide chains with molecular weights of 95 000 and 110 000. The amino acid composition is reported. As in the haemocyanins, the N-terminus is blocked. The carbohydrate content is 0.9%, glucose being the only sugar identified.

gamma-Carboxyglutamic acid distribution

The distribution of the vitamin K-dependent amino acid, gamma-carboxyglutamic acid was examined in proteins from a variety of sources. Proteins examined include purified rat and bovine coagulation proteins, barium citrate-adsorbing proteins from trout plasma, lamprey plasma, earthworm hemolymph, army worm hemolymph, lobster hemolymph, E. coli B/5, soybean leaf, the protein lysate from the hemolymph cell of the horseshoe crab and parathyroid extract. Other purified proteins examined included human alpha-1-antitrypsin, pepsinogen, S-100, fetuin, tropomyosin-troponin and complement protein C-3. Of these, only the blood-cotting proteins and the vertebrate plasma samples were shown to contain gamma-carboxyglutamic acid.

Isolation and characterization of insect vitellogenin. Its identity with hemolymph lipoprotein II

Several years ago, we isolated two major lipoproteins from the pupal hemolymph of the Cynthia silkworm, both of which contained diacylglycerol as a major lipid, and named them lipoproteins I and II. In this paper, we present definite evidence that the vitellogenin (female protein) of this insect is indeed identical with lipoprotein II.

[Protein composition of hemolymph from the crabs Carcinus mediterraneus Czerniavsky, healthy or parasitized by Sacculina carcini Thompson]

The proteic composition of haemolymph from C. mediterraneus varies during the intermoult cycle. Some proteic fractions are occasionally absent in post-ecdysis. At each intermoult stage, parasitized Crabs have generally the same protein pattern as healthy ones, but the presence of the observed fractions is not constant. Compared healthy Crabs, the sacculinized animals show a surnumerary proteic fraction. With very short delay, the injection of ecdysterone puts the proteic composition of haemolymph from sacculinized Crabs in order, this composition becomes comparable to that from healthy individuals.

Glucagon-like and insulin-like hormones of the insect neurosecretory system

Aqueous extracts of corpus cardiacum-corpus allatum complexes of the adult tobacco hornworm Manduca sexta produced both glycogenolysis and hypoglycaemia when injected into the larval form of the same species. Application of specific radioimmuno assays to similar extracts showed also that these gland complexes contain both glucagon-like and insulin-like peptides. Further, the partially purified immunoreactive peptides had the expected biological activities. The former decreased the glycogen content of the fatbody and the latter the circulating trehalose levels in recipient animals. These results suggest the existence of hormones in these invertebrates having both biological and structural similarities to vertebrate insulin and glucagon.

Production of heteroagglutinins in haemocytes of Leucophaea maderae L

It was our purpose to study the immunological activity of circulating fluid cells in the blattoid insect Leucophaea maderae L. These cells are generically called haemocytes; after a preliminary morphological study under optical microscope, they were treated with anti-heteroagglutinins serum marked with fluorescein isothiocyanate. Thus, it was possible to show the presence of heteroagglutinins into the cytoplasm, as regards one group of haemocytes, and on the cell membrane for the second group.

Horomonal control of larval diapause and metamorphosis of the southwestern corn borer Diatraea grandiosella

Changes in haemolymph juvenile hormone (JH) concentrations of larvae of the southwestern corn borer, Diatraea grandiosella, were used to estimate the activity of the corpora allata. The haemolymph of penultimate nondiapause instars contained a maximum JH titre of 3000 Galleria units (GU)/ml, whereas the titre in the final instar had dropped to 140 GU/ml within 6 h of the ecdysis and continued to remain low. Corpora allata of last-stage non-diapause larvae therefore remain inactive. Some signal other than a rapidly declining JH titre in mid-instar triggers the release of ecdysiotropin because the pupal moulting cyclic did not become independent of the brain and ecdvsial glands until 4–25 and 4–75 days after the final larval ecdysis, respectively. Newly diapaused immaculate larvae had a haemolymph JH titre of ca. 1500 GU/ml. Three JH mimics applied to early last stage non-dispause larvae induced the formation of the immaculate dispause morph. The mimics did not activate the recipient's corpora allata, but elevated the function JH concentration, each having a different intrinsic hormonal activity. Threshold JH concentrations which control larval ecdyses, dispause maintenance, and metamorphosis are presented.

The juvenile hormones in blood of larvae and adults of Manduca sexta (Joh.)

The juvenile hormones (JH) in extracts of Manduca sexta blood were converted to 10-(2,4-dichlorobenzoyloxy)-11-methoxy derivatives and quantitatively determined by gas chromatography with electron capture detection. Early IVth instar larvae contained 0.62 ng JH-I, 1.1ng JH-II and 0.07 ng JH-III per ml blood. Early Vth instar larvae, and adult of both sexes contained the hormones in concentration from 0 to 0.24 ng/ml blood. No hormone was detected in late Vth instar (wandering) larvae. The detection limit in our experiments was less than or equal to 0.003 ng/ml blood.

Genetics of lucilin, a storage protein from the sheep blowfly, Lucilia cuprina (Calliphoridae)

Lucilin, the main storage protein of larval fat body and hemolymph in the sheep blowfly, Lucilia cuprina, has been isolated as a series of trimers composed of subunits of 83,000 +/- 5%, daltons. Extensive electrophoretically detectable polymorphism of lucilin subunit patterns occurs in wild and laboratory populations of Lucilia; from four to nine bands are seen in any one individual. Evidence from genetic, electrophoretic, immunological, and structural studies suggests the existence of a series of 12 or more closely related structural loci (designated Luc-1 to Luc-12) which may have arisen through gene duplication. Codominant allelic variation has been found at several of these loci. Luc-1 and Luc-3, and probably the other structural loci of the series, are located on chromosome 2.

Insect immunity. 11. Simultaneous induction of antibacterial activity and selection synthesis of some hemolymph proteins in diapausing pupae of Hyalophora cecropia and Samia cynthia

We have previously shown that pupae of the giant silkmoth Samia cynthia have a humoral antibacterial activity, which was induced by viable, nonpathogenic gram-negative bacteria (H.G. Boman et al., 1974). We show here that this activity was formed simultaneously with a selective incorporation of amino acids into eight polypeptide chains characterized by their electrophoretic behavior. If actinomycin D or cycloheximide were given at an early time, no antibacterial activity was found. If the inhibitors were given at the time of maximum activity, there was no effect with actinomycin D but a rapid decrease of the activity in the case of cycloheximide. The results imply that the messenger ribonucleic acid was stable, but that at least one protein component was turning over. Hemolymph from immunized pupae of another giant silkmoth, Hyalophora cecropia, was fractionated by ammonium sulfate precipitation. This procedure, together with the isotope distribution after co-electrophoresis in polyarylamide gels, was used for comparing the response to injury and to different infections. Almost identical polypeptide patterns were obtained as a response to an infection with either viable Enterobacter cloacae or Bacillus subtilis. These patterns differed both qualitatively and quantitatively from the injury effect created by an injection as such. There was only a low antibacterial activity in each of the four fractions obtained by ammonium sulfate precipitation. However, a combination of three fractions restored a high killing activity. Fractionation of hemolymph from untreated pupae provided evidence for at least one preexisting factor which stimulated the killing of Escherichia coli. The osmotic pressure of the bacteria contributed to the antibacterial activity towards E. coli, but not towards B. subtitlis. The killing of E. coli was inhibited by liped A and, to a lesser extent, by an inhibitor of proteolytic enzymes. The similarities and differences with the mammalian complement system are discussed.

[Cytochemical observations of hemocytes in decapod brachyuran crustacea (author's transl)]

Hemocytes from two species of crabs, Eriocheir sinensis and Carcinus maenas, have been submitted to different cytochemical reactions in order to bring out the nature of granules' content, either by specific coloration or be enzymatic digestion. Light as well as electron microscopy has been used. The granules appeared to be made essentially of basic proteins, rich in arginin and disulfide bridges but poor in tyrosin. These proteins are linked with nonglycogenic carbohydrates. Glycogen deposits of varied size are restricted to the cytoplasm in all the different cell-types but have never been detected inside the granules themselves. Lipids are poorly represented. The bulk of the granule material is made of neutral mucopolysaccharides although minute amounts of acid mucosubstances could be found in some instances.