Factors affecting the elicitation of sesquiterpenoid phytoalexin accumulation by eicosapentaenoic and arachidonic acids in potato

Eicosapentaenoic and arachidonic acids in extracts of Phytophthora infestans mycelium were identified as the most active elicitors of sesquiterpenoid phytoalexin accumulation in potato tuber slices. These fatty acids were found free or esterified in all fractions with elicitor activity including cell wall preparations. Yeast lipase released a major portion of eicosapentaenoic and arachidonic acids from lyophilized mycelium. Concentration response curves comparing the elicitor activity of the polyunsaturated fatty acids to a cell-free sonicate of P. infestans mycelium indicated that the elicitor activity of the sonicated mycelium exceeded that which would be obtained by the amount of eicosapentaenoic and arachidonic acids (free and esterified) present in the mycelium. Upon acid hydrolysis of lyophilized mycelium, elicitor activity was obtained only from the fatty acid fraction. However, the fatty acids accounted for only 21% of the activity of the unhydrolyzed mycelium and the residue did not enhance their activity. Centrifugation of the hydrolysate, obtained from lyophilized mycelium treated with 2n NaOH, 1 molarity NaBH₄ at 100°C, yielded a supernatant fraction with little or no elicitor activity. Addition of this material to the fatty acids restored the activity to that which was present in the unhydrolyzed mycelium. The results indicate that the elicitor activity of the unsaturated fatty acids is enhanced by heat and base-stable factors in the mycelium.     

Studies on the relationship between glycerophosphoglycolipids and lipoteichoic acids. IV. Trigalactosylglycerophospho-acylkojibiosyldiacylglycerol and related compounds from Streptococcus lactis Kiel 42172.

Streptococcus lactis Kiel 42172 contains at least six unusually polar glycerophosphoglycolipids. The predominant one was composed of D-galactose, D-glucose, glycerol, acyl groups and phosphorus in a molar ratio of approx. 3 : 2 : 2 : 3 : 1. By analysis of the breakdown products of HF hydrolysis and Smith-degradation the structure was established to be [Galp (alpha 1 leads to 6)Galp(alpha 1 leads to 3)-sn-glycero(2 comes from 1 alpha Galp)-1-phospho] leads to 6Glcp(alpha 1 leads to 2), acyl leads to Glcp(alpha 1 leads to 3)-acyl2Gro. By HF hydrolysis the other compounds were shown to be in the main also derivatives of GroP leads to 6Glc(alpha 1 leads to 2), acyl leads to 6Glc(alpha 1 leads to 3)acyl2Gro but they released as water-soluble glycosides Gal(alpha 1 leads to 2)Gro, Gal(alpha 1 leads to 3)Gro, Gal(alpha 1 leads to 3)Gro(2 comes from 1 alpha Gal), Gal(alpha 1 leads to 6)Gal(alpha 1 leads to 3)Gro and Gal(alpha 1 leads to 6)Gal-(alpha 1 leads to 6)Gal(alpha 1 leads to 3)Gro(2 comes from 1 alpha Gal), respectively. In the lipid extract Glc(alpha 1 leads to 2), acyl leads to 6Glc(alpha 1 leads to 3)acyl2Gro and GroP leads to 6Glc(alpha 1 leads to 2), acyl leads to 6Glc(alpha 1 leads to 3) acyl2Gro were also observed. This set of compounds is proposed to constitute a biosynthetic series reflecting the individual steps in the synthesis of the lipoteichoic acid of Streptococcus lactis Kiel 42172 which is made up by the same lipid anchor and a non-classical poly(galabiosyl, galactosyl glycerophosphate)-chain (Koch, H.U. and Fischer, W. (1978) Biochemistry 17, 5275--5281).     

Photosensory transduction in Euglena gracilis: Effect of some metabolic drugs on the photophobic response

We have investigated the effect of some metabolic drugs, 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU), 2,4-dinitrophenol (DNP), sodium azide (NaN₃), on the photobehavior of single cells of Euglena gracilis, in order to clarify the relevance of different metabolic pathways in the process of photoperception and sensory transduction in this alga. The results obtained show that the photophobic response of Euglena is not affected by the action of these drugs. This suggests that neither the photosynthetic process nor oxidative phosphorylation play a significant role in the phenomenon of photosensory transduction in Euglena.List of Abbreviations DNP 2,4-dinitrophenol - DCMU 3-(3,4-dichlorophenyl)-1,1-dimethylurea - PSI Photosystem I - PSII Photosystem II     

Amino acid sequence at the phosphorylated site of rat liver pyruvate kinase

One dominating peptic phosphopeptide, Asx-Thr-Lys-Gly-Pro-Glx-Ile-Glx-Thr-Gly-Val-Leu-Arg-Arg-Ala-(³²P)SerP-Val-Ala-Glx-Leu, was obtained from rat liver pyruvate kinase (type L) phosphorylated by cyclic 3′,5′-AMP-stimulated protein kinase from the same tissue. The sequence around the phosphorylated serine residue is similar to that of a corresponding but smaller peptic phosphopeptide previously isolated from pig liver (type L) pyruvate kinase, Leu-Arg-Arg-Ala-(³²P)SerP-Leu.     

Palatal dimensions in 45,X-females

Seventy-two females with 45,X-chromosome complement were examined for palatal dimensions, and the results of the measurements were compared to those of first-degree normal female relatives of the study subjects and population control females. Hard stone casts were prepared for measuring widths and lengths of the maxillary alveolar arch and palatal height between or at the level of the permanent canines, first and second premolars, and first molars with a palatometer and sharp-pointed vernier calipers (0.5 mm). According to the analyses of covariance (history of orthodontic treatment and loss of permanent teeth as cofactors and age as covariate), the differences in palatal dimensions between the groups were statistically significant or highly significant for all dimensions except for palatal height in the posterior segments. The group of the 45,X-females had the highest mean value for palatal height at the level of the canines and systematically the lowest mean values for palatal width in all segments, while no clear difference could be found in the length of the alveolar arch between the 45,X-females and the relatives, the population control group showing the lowest value in the posterior segments. The findings of this study indicate that the narrowed palate rather than the high palate is a frequent but not definite feature in 45,X-females. This may reflect the effect of sex-chromosomes on width but not other dimensions of the palate, resulting in deficiency of transversal growth of the palate possibly through decreased growth of the palatal shelves or through disturbances in the growth of the nasal septum, sutural growth, or--to which the exostosis on the palatal alveolar plates would refer--disturbances in apposition-resorption growth changes of the maxilla.     

A Lead ANRIL Polymorphism Is Associated with Elevated CRP Levels in Periodontitis: A Pilot Case-Control Study

Elevated high sensitive C-reactive protein (hsCRP) is a marker for systemic inflammation and a risk marker for atherosclerotic cardiovascular disease (ACVD), and has also been associated with periodontitis. Inter-individual variation for hsCRP in periodontitis has been shown. ANRIL is the strongest genetic susceptibility locus for both periodontitis and ACVD, and it is speculated that genetic variation in ANRIL may modulate inflammatory processes. Therefore, we explored the possible association between hsCRP plasma levels and a leading ANRIL single nucleotide polymorphism (SNP) in periodontitis patients and controls. 171 healthy subjects with North European descent (115 periodontitis and 56 controls) were included in this case-control study. hsCRP levels were determined and subjects were genotyped for the leading ANRIL SNP rs1333048. In a multivariate analysis, periodontitis, female gender, increasing BMI and homozygosity for the major allele (AA-genotype) of rs1333048 were significantly associated with elevated hsCRP plasma levels (p = 0.012, p = 0.004, p = 0.007 and p = 0.003, respectively). Periodontitis patients with rs1333048 AA-genotype showed higher levels of hsCRP than those carrying the minor C allele (median: 4.5 mg/L vs. 1.6 mg/L, p_adjusted = 0.007). This study is the first to show that, in addition to gender and BMI, also a leading SNP in ANRIL is explanatory for inter-individual variation in hsCRP levels in periodontitis patients of North European descent.     

Recovery of evergreen clonal dwarf shrubVaccinium vitis-idaea after simulated microtine herbivory in a boreal forest

The evergreen dwarf shrub lingonberry (Vaccinium vitis-idaea L.) was subjected to microtine herbivory simulations to investigate its recovery in a boreal forest. Beside the control (A), the study included three levels of herbivory: clipping of half the annual branches from 50% of ramets (B), removal of 50% of ramets (C), and removal of 100% of ramets (D). Density, growth, and fecundity of the ramets were monitored during the study. New ramets emerged rapidly from dormant basal buds at the base of the removed ramets in groups C and D. After three growth seasons, 60–117% and 42–112% of density and biomass, respectively, had been regained in the groups damaged relative to the control, the difference being insignificant between the treated groups apparently because of the small sample size. Survival, fecundity and net growth of ramets were not affected by the treatment. Mean dry weight of annual branches in new ramets was lower in the damaged groups than the control. The recovery of the lingonberry was unexpectedly good. The results suggest that, since natural herbivory seldom is as heavy as in this work, the time between population density peaks of microtine rodents is usually long enough for the lingonberry to recover in boreal ecosystems.