Interstrain variation of murine arylsulfatase C

Summary A method has been developed for the assay of arylsulfatase C in tissue extracts containing arylsulfatases A and B. Significant variation of enzyme activity was observed among 26 inbred murine strains. Activity differences were apparent at all stages evaluated between 1 and 70 days postnatal age. Arylsulfatase C from representative high- and low-activity strains exhibited similar Michaelis constants, temperature optima, pH optima, thermostabilities and inhibitor profiles.This work was supported in part by Biomedical Sciences Support Grant: HEW PHS RR 07030.     

Zur Frage des pH-Optimums des Pepsins

Summary Natural and purified proteins were split by crystallized pepsin. The break down of substrates was followed by a turbidimetric method. pH optima were found from 1.5 to 3.8. Only unpurified egg albumin had two optima, crystallin had one in the acid range. Ovomucoid not being split by pepsin, the second peak at pH 3.79 is referred to conalbumin. While the disintegration of caseinogen becomes slow with decreasing acidity, this is not true for casein (paracasein) which is well split up to pH 3.28 (cows casein) or 3,73 (womens casein). Nevertheless, the optimum is in the range of 1.5–2.0, like most proteins. Above this limit, the following optima were found: fibrinogen 2.93, thrombin 2.78, edestin 3.08, crystallized hemoglobin 3.19, conalbumin 3.79.     

Bacterial lipopolysaccharide (LPS) enhances concanavalin A reactivity of thymocytes from the low-LPS-responder mouse strain C3H/Hej.

The capacity of LPS to enhance Con A reactivity of thymocytes was studied comparatively in the low-LPS-responder C3H/Hej mice and the high-LPS-responder CBA mice. The extent of synergism LPS + Con A was found similar in both strains.     

Renewal of noradrenaline in different zones of the central nervous system of inbred mice strains and their recombinants]

A good correlation exists between the learning capacity and norepinephrine metabolism in the neocortex of C57 and Balb inbred Mice strains, as well as their F1 hybrids and seven recombinant inbred strains derived from their cross. The animals with a better learning performance are characterised by low levels of norepinephrine, as well as a slow metabolic rate of this neurotransmitter in the cortex. Such a correlation has not been found to exist in the other cerebral regions studied.     

Immunostimulating lipopeptide,LtriP (RP 56142): Comparison of the effect on hepatic cytochrome P 450 modulation and radioprotection in male and female of three mouse strains

The sex-dependent effect of lauroyl-L-Ala-D--Glu-L,L-A₂pmNH₂ (LtriP, RP 56142) on hepatic microsomal cytochromes P 450 (cyt P 450) was studied in three mouse strains NMRI, C3H/OuJ and C3H/HeJ. In NMRI and C3H/OuJ, strains which are responsive to bacterial lipopolysaccharides (LPS-responsive), regardless of the sex of the mouse, significant decrease in the amount of cyt P 450 was observed after LtriP treatment, with a concomitant reduction in ethoxyresorufin-O-deethylase (cyt P 450 1A-dependent) and 7-ethoxycoumarin-O-deethylase activities. This was not seen in C3H/HeJ (LPS-hyporesponsive) mice. These effects may be related to LtriP-dependent cytokine induction, since neither LtriP nor LPS stimulated interleukin-1 (IL-1) secretion by C3H/HeJ macrophages. 11- and 12-hydroxylations (11- and 12-OH) of lauric acid were compared in C3H/OuJ and C3H/HeJ mice. LtriP depressed the total enzymatic conversion of lauric acid in the two strains without modification of the 11/12-OH ratio for C3H/OuJ or male C3H/HeJ mice. However, in females C3H/HeJ mice this decrease was particularly significant and concerned especially the 12-OH activity (a marker of cyt P450 4A family). Although males of the three strains were more sensitive to irradiation than females, LtriP exerted a sex-independent radioprotection on NMRI and C3H/OuJ mice. Its radioprotective effect was illustrated by the preservation of all the enzymatic activities studied in treated NMRI mice, contrary to irradiated control animals. In contrast, for the C3H/HeJ strain, males were not protected by LtriP treatment and, furthermore, females showed a marked sensitization to irradiation.The effects in CH3/HeJ strain implicate LtriP in the control of cyt P 450 induction and of sensitivity to irradiation independently of IL-1 induction.     

Bacterial lipopolysaccharide (LPS) enhances concanavalin A reactivity of thymocytes from the low-LPS-responder mouse strain C3H/Hej

Summary The capacity of LPS to enhance Con A reactivity of thymocytes was studied comparatively in the low-LPS-responder C3H/Hej mice and the high-LPS-responder CBA mice. The extent of synergism LPS+Con A was found similar in both strains.This work was supported by a grant from the INSERM (CRL: 76-5-101-1).     

Arylsulfatase B synthesis and clearance in inbred mouse strains

Arylsulfatase B activity levels were approximately 2-3-fold higher in adult C57BL/6J liver and kidney compared to corresponding tissues from A/J inbred mice. In vivo incorporation of tritiated leucine into C57BL/6J hepatic arylsulfatase B reached a maximum approximately 15 h after injection. The label was cleared from C57BL/6J arylsulfatase B with an apparent half-life of 36 h. The relative rates of synthesis of C57BL/6J and A/J arylsulfatase B were similar; however, the A/J enzyme was cleared more rapidly from liver tissue. C57BL/6J kidney arylsulfatase B appeared to be synthesized at a 2-3-fold higher rate than the corresponding A/J enzyme. These trends suggest genetic regulation of arylsulfatase B is effected through different means in liver and kidney from adult mice of these two inbred strains.     

Opioids and behavior: genetic aspects

Summary Three animal models, based on genetic differences in endogenous opioid peptides and opioid receptors, are described. Obese mice and rats, whose pituitary opioid content is elevated, may be used to investigate eating disorders. Recombinant inbred strains of mice, which differ in brain opioid receptors and analgesic responsiveness, can be used for study of opioid-and nonopioid-mediated mechanisms of pain inhibition. Individual reactivity to opioids can be examined in C57BL/6 and DBA/2 inbred strains of mice. A model that combines a variety of opioid effects is offered and suggests the existence of a genetically determined dissociation of opioid effects on locomotor activity and pain inhibition. In addition, stimulatory locomotor responses in the C57BL/6 reaction type are linked to a high risk of drug addiction and facilitatory effects on adaptive processes, while high analgesic potency in the DBA/2 reaction type is accompanied by a low proneness to drug abuse and amnesic properties of opioids.     

Opioids and behavior: genetic aspects

Three animal models, based on genetic differences in endogenous opioid peptides and opioid receptors, are described. Obese mice and rats, whose pituitary opioid content is elevated, may be used to investigate eating disorders. Recombinant inbred strains of mice, which differ in brain opioid receptors and analgesic responsiveness, can be used for study of opioid- and nonopioid-mediated mechanisms of pain inhibition. Individual reactivity to opioids can be examined in C57BL/6 and DBA/2 inbred strains of mice. A model that combines a variety of opioid effects is offered and suggests the existence of a genetically determined dissociation of opioid effects on locomotor activity and pain inhibition. In addition, stimulatory locomotor responses in the C57BL/6 reaction type are linked to a high risk of drug addiction and facilitatory effects on adaptive processes, while high analgesic potency in the DBA/2 reaction type is accompanied by a low proneness to drug abuse and amnesic properties of opioids.     

Transfer of the tetracycline-chloramphenicol plasmid in Clostridium perfringens]

Two plasmids which confer resistance to Tetracycline-Chloramphenicol and Erythromycine-Clindamycine were found in a strain of Clostridium perfringens. The plasmid (Tet-Chl) was shown to be transferable to sensitive strains of C. perfringens. The transfer experiments were made with the wild type strain or strains cured by one plasmid or the other as donor strains.     

Changes in brain dopamine levels and aggressive behavior with aging in 2 mouse strains

The genetic programming of brain monoamine changes with aging show remarkable differences in 2 mouse strains. A marked increase in dopamine occurred in 32-week-old grouped ICR mice and the males showed intense irritability and aggressive behavior. Brain amines changed only slightly in old C57BL6J mice and behavior remained benign. Old females showed similar amine changes but aggresive behavior did not occur in either strain.     

Changes in brain dopamine levels and aggressive behavior with aging in 2 mouse strains

Summary The genetic programming of brain monoamine changes with aging show remarkable differences in 2 mouse strains. A marked increase in dopamine occurred in 32-week-old grouped ICR mice and the males showed intense irritability and aggressive behavior. Brain amines changed only slightly in old C57BL6J mice and behavior remained benign. Old females showed similar amine changes but aggressive behavior did not occur in either strain.     

What determines the population size of the intracellular algal symbionts in the digestive cells of green hydra?

Summary The ratios of algal volume to amount of host protein in 5 strains of green hydra were found to be closely similar. However, the components of algal volume varied in the 5 strains, suggesting differences in interactions between animal and algal growth rates.Acknowledgements. This work was supported by an N.E.R.C. postgraduate research grant. I would like to thank Professor D.C. Smith, F.R.S., for his invaluable help in drafting this paper.     

Antimicrobial activity of carbazole derivatives

Summary Glycozoline and girinimbine isomers (IV andVII) were synthesized and their activity against 2 bacterial strains, viz.E. coli andS. aureus, and 2 fungal strains, viz.C. albicans andA. niger were studied. The hydroxy synthons (III) were also tested. The authors are thankful to Dr B.N. Apte, Association of Microbiologists of India, Bombay Unit, for providing some of the organisms, to Prof. A.K. De, Indian Institute of Technology, for financial assistance, to Prof. G. D. Shah, Department of Chemistry, Indian Institute of Technology for guidance, encouragement and helpful discussions.     

An extremely cadmium-sensitive strain ofChlorella

Summary Growth of 14 strains from fiveChlorella species is rather insensitive towards cadmium. One strain (211-1a) ofC. saccharophila, however, was found to have a sensitivity towards this toxic heavy metal about 100 times higher than that of the other strains ofC. saccharophila.Acknowledgment. For excellent technical assistance I am indebted to Mrs U. Knoch and Mrs E. Weitemeyer.     

Different action of alpha-methyl-DOPA on sleep and labyrinth learning in 2 inbred strains of mice]

In two inbred mice strains C 57 BR and C 57 BL/6 presenting the same type of sleep, but a different capacity of learning, Alpha-Methyl-Dopa (100 mg/kg) injected after every session, suppresses paradoxical sleep completely for 9 to 11 h. Maze-learning performance is retarded in C 57 BR mice, but facilitated in C 57 BL/6.     

The inability of nuclear dehydrogenating clostridia to oxidize bile salt hydroxyl groups.

In a survey of the intracellular bile salt oxidoreductase activity in fecal bacteria, 16 strains of nuclear dehydrogenating clostridia and 2 strains of non-nuclear dehydrogenating C. paraputrificum were demonstrated unable to oxidize cholate at any of the 3 OH groups. Since nuclear dehydrogenation at the delta-1 and delta-4 position requires a 3-oxo precursor steroid, it appears that these organisms require the presence of a 3 alpha-hydroxysteroid dehydrogenating organism for nuclear dehydrogenation.     

An agglutinin with unique specificity for N-glycolyl sialic acid residues of thyroglobulin in the hemolymph of a marine crab Scylla serrata (Forskal).

A novel agglutinin with specificity for sialic acid sequence of sugars in thyroglobulin is identified in the hemolymph of Scylla serrata. The physico-chemical characteristics of its binding affinity, such as pH and temperature optima, and cationic requirements are defined. N-glycolyl neuraminic acid (NeuGc) (at 0.6 mM), in contrast to N-acetyl neuraminic acid (NeuAc) (at greater than 5.0 mM), is the potent inhibitor of hemagglutination. Bovine and porcine thyroglobulins containing NeuGc, inhibited the agglutination. NeuGc-acid glycoprotein fraction (bovine) but not NeuAc-acid glycoprotein fraction (human) inhibited the hemagglutination. The inability of other NeuGc-glycoproteins (bovine submaxillary mucin) to inhibit the agglutination suggests that the agglutinin may also recognize glycosidic linkage associated with NeuGc. The potential of the agglutinin in identifying NeuGc containing human tumor associated antigens is discussed.     

Genotype-specific reduction in methyl nitrosourea (MNU) induced sister chromatid exchanges (SCE) in vivo during aging

We studied mice from five strains (BALB/c, C3H/HeSnJ, C57BL/6J, Csb and 129/ReJ) at two ages (young, 10 +/- 1 weeks; and old, 67 +/- 3 weeks) for the induction of sister chromatid exchanges (SCEs) in vivo by methyl nitrosourea (MNU). The SCE frequency is genotype-specific. The F1 phenotype resembles the 'low' responding parent. SCE induction is significantly lower in the older animals of each strain than their younger counterparts, and the reduction of SCE/cell with old age is strain-specific. A general explanation for these results must include strain differences in relative mutagenic sensitivity, genotype-specific pattern of reduction in DNA repair and other such factors affecting SCE formation, with old age.     

An agglutinin with unique specificity for N-glycolyl sialic acid residues of thyroglobulin in the hemolymph of a marine crabScylla serrata (Forskal)

A novel agglutinin with specificity for sialic acid sequence of sugars in thyroglobulin is identified in the hemolymph ofScylla serrata. The physico-chemical characteristics of its binding affinity, such as pH and temperature optima, and cationic requirements are defined. N-glycolyl neuraminic acid (NeuGc) (at 0.6 mM), in contrast to N-acetyl neuraminic acid (NeuAc) (at >5.0 mM), is the potent inhibitor of hemagglutination. Bovine and porcine thyroglobulins containing NeuGc, inhibited the agglutination. NeuGc-acid glycoprotein fraction (bovine) but not NeuAc-acid glycoprotein fraction (human) inhibited the hemagglutination. The inability of other NeuGc-glycoproteins (bovine submaxillary mucin) to inhibit the agglutination suggests that the agglutinin may also recognize glycosidic linkage associated with NeuGc. The potential of the agglutinin in identifying NeuGc containing human tumor associated antigens is discussed.