The carotenoids of eggs of wild and farmed cod (Gadus morhua)

• 1.1. Eggs of wild cod, and of farmed cod fed (a) a diet supplemented with astaxanthin and (b) a diet supplemented with both astaxanthin and canthaxanthin, were analysed with respect to carotenoids.
• 2.2. The total carotenoid contents in eggs were 0.7 ppm for wild cod and 0.5 ppm for farmed cod.
• 3.3. Cod, having white flesh, deposit ketocarotenoids in the eggs, preferably astaxanthin.
• 4.4. Canthaxanthin can replace astaxanthin in the eggs, but astaxanthin appears to be deposited preferentially when both carotenoids are present in the diet.
• 5.5. The isomer distribution of (3S, 3′S):(3R, 3′S, meso):(3R, 3′R) astaxanthin in the eggs reflected the isomer composition of the diet.
• 6.6. Echinenone, 4′-hydroxyechinenone, adonixanthin and zeaxanthin encountered in cod eggs may represent reductive metabolites of canthaxanthin and astaxanthin.

     

Domain structure of the 90-kDa stress protein: Heparin- and antibody-binding domain

• 1.1. To understand the physiological roles of the 90-kDa stress protein (HSP90), we investigated the heparin- and antibody-binding domains of the protein.
• 2.2. For heparin-binding sites, HSP90 was digested completely with trypsin, and the digests were applied to a heparin-Sepharose column and eluted with 1.0 M NaCl, followed by 8.0 M urea.
• 3.3. Each elutant was purified by a reverse-phase C₁₈ column.
• 4.4. Two peptides from the NaCl-eluted fraction and no peptide from the urea-eluted fraction were purified.
• 5.5. The purified peptides were sequenced by an automated peptide sequencer.
• 6.6. One of the heparin-binding sites was present between Leu-362 and Arg-365; another was present between Leu-645 and Lys-648.
• 7.7. These two peptides were basic and considerably hydrophilic.
• 8.8. For antibody-binding sites, HSP90 was mildly digested with trypsin, electrophoresed on SDS-polyacrylamide gels and transferred to PVDF membranes.
• 9.9. The four bound of the trypsin fragments could be sequenced with a peptide sequencer.
• 10.10. There was only one antibody-binding peptide, 38 kDa, starting from Pro-2. The others showed no cross-reactivity with the antibody and started from Leu-283.
• 11.11. Therefore, the epitopes of HSP90 are present between Pro-2 and Leu-282.
• 12.12. The heparin-binding sites are present from the middle region of the HSP90 molecule, and the antigen sites are at the N-terminal domain.

     

Characterization of glutathione S-transferases in a solitary bee,Megachile rotundata (Fab.) (hymenoptera: megachilidae) and inhibition by chalcones,flavone, quercetin and tridiphane-diol

• 1.1. The glutathione S-transferases of Megachile rotundata (Fab.) were characterized eletrophoretically and spectrophotometrically.
• 2.2. Differences were found between sexes with respect to number of isozymes and activity with age.
• 3.3. Inhibition patterns of chalcone, seven of its synthetic derivatives, flavone, quercetin, and tridiphanediol differed with respect to sex and substrate.
• 4.4. Comparisons are made with the honey bee, Apis mellifera L.

     

Catalytic and inhibitory properties of a major molecular form of acetylcholinesterase isolated from Lygus hesperus knight (Hemiptera: Miridae)

• 1.1. The major form of acetylcholinesterase (AChE) from Lygus hesperus demonstrated a greater affinity to selected substrates than unresolved AChE.
• 2.2. The turnover numbers of the native AChE were 7000 min⁻¹ for acetylthiocoline, 4800 for acetyl-(β-methyl) thiocholine, 3000 for propionylthiocholine, and 390 for S-butyrylthiocholine.
• 3.3. Each molecule of the major form had two active sites and each subunit had one active site.
• 4.4. Paraoxon or dichlorvos had a higher affinity to the major AChE form than to the unresolved AChE, resulting in a higher potency for the inhibition.
• 5.5. Some references of comparison are also made with AChE from other animal species.

     

Ostrich fructose-1,6-bisphosphatase: Kinetic characterization of the liver isoenzyme

• 1.1. Purified ostrich (Struthio camelus) liver fructose-1,6-bisphosphatase exhibited an absolute requirement for Mg²⁺.
• 2.2. The enzyme catalyzed the hydrolysis of fructose-1,6-bisphosphate, sedoheptulose-l,7-bisphosphate and ribulose-l,5-bisphosphate.
• 3.3. S_0.5 for substrate was 1.4 μM.
• 4.4. AMP was a potent non-competitive inhibitor with respect to substrate (K_i of 25 μM).
• 5.5. Fructose-2,6-bisphosphate was a potent competitive inhibitor of the enzyme (K_i of 4.8 μM).

     

Kinetic studies of catechol-o-methyltransferase from the brain of the African catfish,Clarias gariepinus

• 1.1. Optimum in vitro conditions, and kinetics of the enzyme catechol-O-methyltransferase from the brain of the male African catfish were studied.
• 2.2. A saturated level for S-adenosylmethionine, as methyldonor, and magnesium as cofactor was reached at 5 μM and 10 mM, respectively.
• 3.3. The addition of ascorbic acid, as an antioxidant, and tranylcypromine, as a MAO inhibitor, was not necessary, during incubations with fore-brain homogenates.
• 4.4. Kinetic analysis of the methylation of catecholestrone, catecholestradiol and dopamine showed K_m values of 1.2, 0.6 and 0.5 μM, respectively.
• 5.5. The affinity of the catecholsubstrates for the enzyme catechol-O-methyltransferase is much higher in the brain of the African catfish than in tissues of mammals.

     

IDentification of a microsomal retinoic acid synthase as a microsomal cytochrome P-450-linked monooxygenase system

• 1.1. To characterize an enzyme which metabolizes retinal in liver microsomes, several properties of the enzymatic reaction from retinal to retinoic acid were investigated using rabbit liver microsomes.
• 2.2. The maximum pH of the reaction in the liver microsomes was 7.6.
• 3.3. The K_m and V_max values for all-trans, 9-cis and 13-cis-retinals were determined.
• 4.4. The reaction proceeded in the presence of NADPH and molecular oxygen.
• 5.5. The incorporation of one atom of molecular oxygen into retinal was confirmed by using oxygen-18, showing that the reaction comprised monooxygenation, not dehydrogenation.
• 6.6. The monooxygenase activity was inhibited by carbon monoxide, phenylisocyanide and antiNADPH-cytochrome P-450 reductase IgG, but not by anti-cytochrome b₅ IgG.
• 7.7. The enzymatic activity inhibited by carbon monoxide was photoreversibly restored by light of a wavelength of around 450 nm.
• 8.8. The retinal-induced spectra of liver microsomes with three isomeric retinals were type I spectra.
• 9.9. The microsomal monooxygenase activity induced by phenobarbital or ethanol were more effective than that by 3-methylcholanthrene, clotrimazole or β-naphthoflavone.
• 10.10. These results showed that the monooxygenase reaction from retinal to retinoic acid in liver microsomes is catalyzed by a cytochrome P-450-linked monooxygenase system.

     

Responses of antioxidants and lipid peroxidation in mussels to oxidative damage exposure

• 1.1. The aim of this work was to evaluate the relationships between free radical scavengers and lipid peroxidation in the common mussel Mytilus edulis.
• 2.2. Mussels were exposed to compounds known for their ability to produce free radicals (carbon tetrachloride, CCl₄) and reactive oxygen species via redox cycling (menadione), and the effects on digestive gland, gills and remaining tissues were studied.
• 3.3. Lipid peroxidation parameters and the status of free radical scavengers (glutathione, vitamins A, E and C) were affected more by exposure to menadione than to CCl₄.
• 4.4. The observed changes in the free radical scavengers content are indicative of a role in detoxication of damaging reactive species.

     

Breast,hips, and buttocks revisited: Honest fatness for honest fitness

This paper comments on: Low, B. S., Alexander, R. D., and Noonan, K.M. Human hips, breast, and buttocks: Is fat deceptive? Ethology and Sociobiology 8: 249-247, 1987. In it I argue that:

• 1.1. Sexual selection has probably not been the most important selection pressure on
• 2.female human body shape.
• 3.2. Male humans in different cultures find different aspects of the female body attractive
• 4.and therefore are unlikely to have exerted consistent directional sexual selection on
• 5.the female body.
• 6.3. Breast size is not correlated with lactation success.
• 7.4. Visible hip width is not correlated with parturition success.
• 8.5. Women would lower their fitness if they tried to deceive men about their internal
• 9.pelvic dimensions.
• 10.6. There are many alternative hypothesis to explain the existence of fat onwomen's
• 11.breast, hips, and buttocks.

     

Decreased Antibiotic Susceptibility Driven by Global Remodeling of the Klebsiella pneumoniae Proteome

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Highlights

• •Global proteomic remodeling alters antibiotic susceptibility in K. pneumoniae.
• •Drug specific transport, sugar utilization, central metabolism, capsule synthesis.
• •Common pathways of reactive oxygen scavenging, turnover of misfolded proteins.
• •Integrated adjustments and unique drug-specific features for drug combinations.

     

Anaerobic metabolism in sublittoral living Mytilus galloprovincialis in the mediterranean—IV. Role of amino acids in adaptation to low salinities during anaerobiosis and aerobiosis

• 1.1. When Mytilus galloprovincialis were transferred from 38 to 19%. sea water (S), the metabolism became anaerobic for at least 8 hr. After 24 hr the animals were entirely aerobic again.
• 2.2. Upon transfer to 19%. S, the total free amino acid concentration in haemolymph doubled within 4 hr, remaining nearly constant thereafter, up to 48 hr.
• 3.3. In the posterior adductor muscle a strong decrease of alanine and glycine occurred at 48 hr exposure to 19%. S, and a smaller decrease of glutamate; taurine remained relatively constant. When transferred again to 38%. S after 14 days, a strong overcompensation occurred in the concentrations of alanine and proline, and a smaller overcompensation in those of threonine and serine.
• 4.4. In the gill no distinct change in the amino acid pool occurred during 14 days of exposure, with the exception of a decrease in serine. When transferred again to 38%. S, a strong overcompensation occurred in alanine, proline, glycine and serine, and a smaller in glutamate and threonine.
• 5.5. No evidence for anaerobic metabolism in the decrease of the amino acid pool was found.
• 6.6. M. galloprovincialis is less able to adapt to low salinities than the more euryhaline M. edulis.

     

Amino acid sequences around exofacial proteolytic cleavage sites of band 3 from bovine and porcine erythrocytes

• 1.1. Amino acid sequences of bovine and porcine band 3, an erythrocyte anion transporter, were determined.
• 2.2. The sequence of bovine band 3 was positioned to residues 519–599 (the numbering is based on human band 3), in which probably 6 residues were unidentified.
• 3.3. Binding site of DIDS (4,4'-diisothiocyanostilbene-2,2'-disulfonate), a potent anion transport inhibitor, was identified as Lys-539 in the bovine case.
• 4.4. A loop (residues 551–567), which provides exofacial proteolytic cleavage sites, contains only 53% homology between human and bovine, whereas the residues flanking it on either side are >84% homologous.
• 5.5. Furthermore, the loop of porcine band 3 was indicated to consist of a 6 or 7-residues short peptide as compared with those of other species.

     

The flow theory of enzyme kinetics: Role of solid geometry in the control of reaction velocity in live animals

• 1.1. When blood flows, membranes are bombarded with ions etc., whose entry creates an ATP demand proportional to flow rate. Also proportional to flow rate is ATP production from oxidation of substrates [S] from the same blood volume.
• 2.2. O₂ is limiting and reaction velocity at rest (metabolic rate) is determined by flow rate, F, but not by [S].
• 3.3. Since resting blood O₂ A-V difference is about 5 vol%, 11 circulated produces about 0.25 kcal in mammals, birds or warm reptiles.
• 4.4. Where O₂ is not limiting, as in most amino acid deaminations, V = K F[S] with K a constant unrelated to K_m.
• 5.5. At equal blood vol/kg, solid geometry dictates that the average cross-sectional area of major vessels/kg will be an inverse function of body mass. The smaller the animal, the shorter the vessels, the “thicker” the vessels/kg body wt, and at any one blood pressure, the higher the flow/kg/hr. If a man's major vessels were equal in cross-section/kg to those of a shrew, it would take 2241 of blood to fill them.
• 6.6. Growth decreases flow/kg (and therefore metabolic rate), by decreasing vessel cross-section/kg without changing blood pressure or linear velocity of flow.
• 7.7. Surface area/g, body wt to some power, average vessel length/kg, circulation time and average major vessel cross-sectional area are all related mathematically.

     

The compositoin of cuticular hydrocarbons of the cereal aphids Sitobion avenae F. (Homoptera,Aphididae)

• 1.1. The cuticular hydrocarbons of the cereal aphids, Sitobion avenae F. were studyed by capillary column chromatography and mass spectrometry.
• 2.2. n-Alkanes, 2-, 3-, 4-, 5-, 6-, 10-, 11-, 12- and 13-monomethylalkanes, 7,11-, 11,15-, 13,17- and 5,11-dimethylalkanes were found in cuticular lipids.
• 3.3. The results obtained are significantly different from these of pea aphid, where only n-alkanes were found.
• 4.4. The n-alkanes of cereal aphids range from 23 to 35 carbon atoms with the predominance of odd over even members.
• 5.5. These are terminally branched hydrocarbons 2-methyl and 3-methyl-alkanes rarely found together in cuticular lipids of insects.

     

Locust vitellogenin receptor: an acidic glycoprotein with N- and O-linked oligosaccharides

• 1.1. The locust vitellogenin (VTG) receptor which is embedded in oocyte plasma membranes is a glycoprotein.
• 2.2. With various lectins oligosaccharide units have been identified, among them neuraminic acid linked to Gal or GalNAc, mannose chains, Gal linked to GalNAc or GlcNAc and fucose linked to GlcNAc.
• 3.3. With specific enzymes it could be shown that mannose and most other oligosaccharides are O-linked while others like fucose are N-linked.
• 4.4. Enzymatic removal of all O-linked carbohydrates resulted in a drop of the molecular mass of the receptor protein from 200,000 to 110,000.
• 5.5. A total of N- and O-linked oligosaccharides of 54% was calculated.
• 6.6. The isoelectric point of the receptor was found to be at pH 3.4 increasing slightly after removal of neuraminic acid.
• 7.7. Removal of neuraminic acids destroyed the binding ability for VTG.

     

Comparative biochemical studies of carotenoids in sea-urchins—II. The more primitive sea-urchins belonging to the orders Cidaroida,Echinothurioida, Diadematoida and Arbacioida

• 1.1. The carotenoids of seven species of more primitive sea-urchins, [orders Cidaroida (I), Echinothurioida (II), Diadematoida (III), and Arbacioida (IV)] were investigated from the comparative biochemical point of view.
• 2.2. β,β-carotene and β-echinenone have been isolated as major carotenoids in (I) and (III, IV), respectively. In (II), β,β-carotene, β-echinenone, canthaxanthin and (3S,3′S)-astaxanthin were foundto be predominant carotenoids.
• 3.3. The carotenoid patterns of (I) which is the most primitive sea-urchin from the phylogenetic point of view, and of (II) which is direct developers with non-feeding larvae, were quite different from those of the other sea-urchins showing typical development with feeding larvae.

     

Oxidation of methionine residues in equine growth hormone by chloramine-T

• 1.1. Reactivity of methionine residues towards Chloramine-T was studied in the equine growth hormone.
• 2.2. With a 20.0-fold molar excess of reagent over methionine, full oxidation of the four residues of the protein is achieved.
• 3.3. Methionine 4 is the most reactive group, followed by methionines 72 and 178—methionine 123 being the less reactive residue.
• 4.4. As judged by circular dichroism spectra and binding assays, protein conformation and binding capacity to specific receptors remains unchanged even after full oxidation of all four methionine residues.
• 5.5. Results agree with data previously obtained with bovine growth hormone.

     

Effects of temperature and acid stress on hatching,survival capacity,metabolism and postural reflexes in caenid mayflies (ephemeroptera)

• 1.1. Mortality was 100% at pH 3.5 over a temperature range of 10–30°C for embryos and nymphs of Caenis diminuta and C. hilaris.
• 2.2. Hatching success for both species was highest at pH values above 4.5.
• 3.3. Survival capacities were significantly higher at 20°C over a pH range of 4.0-7.2.
• 4.4. Oxygen consumption rates increase as a function of increasing temperature and reduced acidity.
• 5.5. Loss of the nymphal righting response was observed at pH 3.5. This response can be used as a behavioral assay for acid stress.

     

Elementary chemical composition of Tisbe holothuriae humes (copepoda: harpacticoida) as influenced by temperature,salinity and food type

• 1.1. The copepod Tisbe holothuriae was collected from the Saronicos gulf of Greece and cultured in the laboratory, under dif'erent combinations of temperature and salinity and as well as different types of food.
• 2.2. The content of C, H and N in females was measured.
• 3.3. As temperature increases and salinity declines from 38%, the content of C, H and N per individual decreases.
• 4.4. The type of food influences the carbon and hydrogen content per individual, while the nitrogen content is relatively constant.
• 5.5. The percentage content of C, H and N in females without egg sacs and females carrying their first newly formed egg sacs do not differ significantly

.     

Purification and some properties of an atypical alkaline p-nitrophenylphosphate phosphatase activity from Halobacterium halobium

• 1.1. An alkaline p-nitrophenylphosphate phosphatase has been purified 440-fold from extracts of Hatobacterium halobium.
• 2.2. The enzyme has an apparent molecular weight of 24,000.
• 3.3. A K_m value for p-nitrophenylphosphate of 1.12mM has been found under optimal conditions.
• 4.4. The enzyme is selectively activated and stabilized by Mn²⁺.
• 5.5. It requires high salt concentrations for stability and maximum activity.
• 6.6. It displays an unusual restricted substrate specificity of 25 phosphate esters tested, only phosphotyrosine and casein were hydrolysed besides p-nitrophenylphosphate.