Chemotype pattern differentiation of Thymus pulegioides on different substrates

Relationships between soil chemistry and population chemotype structure of Thymus pulegioides have been studied. The analysis of correlations suggest that an increased carbonate content in soil decreases the chemotype diversity of a population (as calculated by use of the Shannon index): the proportion of linalool chemotype plants rises and that of the phenol chemotype plants declines. In addition, the chemotype diversity decreases with increasing frequency of linalool chemotype, and increases with increase of carvacrol chemotype.     

Chemical and serological properties of lipopolysaccharides from Vibrio parahaemolyticus O-untypeable strains isolated from patients

Chemical and serological studies have been carried out on the O-antigenic lipopolysaccharides (LPS) of six strains, U-6443, W-90144, X-3972, AD-7999, 90A-6611 and KX-V212, of Vibrio parahaemolyticus isolated from patients. The O-serotypes of these strains have not been identified because they were not agglutinated by any diagnostic antisera against known O-serotype strains. A compositional sugar analysis of their LPS revealed that out of the six O-untypeable (OUT) strains, U-6443, W-90144 and AD-7999 strains belonged to chemotype II (chemotype of O2), 90A-6611 and KX-V212 strains to chemotype III (chemotype of O3, O5, O11 and O13) and X-3972 strain to chemotype IV (chemotype of O4). A structural analysis of LPS isolated from KX-V212 revealed that the inner core region of the LPS consisted of only one mole of 2-keto-3-deoxy-D-manno-octonic acid, which carried a phosphate group at position C4 and the outer core at position C5. In passive hemolysis tests performed by using LPS as the antigen to sensitize sheep red blood cells (SRBC), and diagnostic antisera (O1 to O11) or anti-whole-cell rabbit antisera raised against O12, O13 and the six OUT strains, strong cross-reactivity was observed among LPS derived from the strains belonging to chemotype II (U-6443, W-90144, AD-7999 and O2). Strong cross-reactivity was also observed between X-3972 (chemotype IV) and O4 LPS. In contrast, LPS from two of the strains belonging to chemotype III (90A-6611 and KX-V212) did not react with any of the antisera raised against known O-serotypes. Cross-absorption tests showed that the O-antigens of U-6443, W-90144 and AD-7999 were identical to that of O2, and the O-antigen of X-3972 to that of O4. On the other hand, after the absorption of antisera raised against 90A-6611 and KX-V212 with O2 cells, the hemolytic activities against SRBC sensitized with homologous LPS were still retained at a high titer, whereas the hemolytic activities against SRBC sensitized with LPS from other O-serotype strains were completely eliminated. A cross-absorption test revealed that the O-antigens of these two strains were identical to each other. Thus, it was demonstrated that the O-serotype of OUT strains 90A-6611 and KX-V212 was not involved in the known O-serotypes; rather it represented a novel serotype which has not hitherto been reported.     

The yeast-phase virulence requirement for α-glucan synthase differs among Histoplasma capsulatum chemotypes

Histoplasma capsulatum strains can be classified into two chemotypes based on cell wall composition. The cell wall of chemotype II yeast contains a layer of α-(1,3)-glucan that masks immunostimulatory β-(1,3)-glucans from detection by the Dectin-1 receptor on host phagocytes. This α-(1,3)-glucan cell wall component is essential for chemotype II Histoplasma virulence. In contrast, chemotype I yeast cells lack α-(1,3)-glucan in vitro, yet they remain fully virulent in vivo. Analysis of the chemotype I α-glucan synthase (AGS1) locus revealed a 2.7-kb insertion in the promoter region that diminishes AGS1 expression. Nonetheless, AGS1 mRNA can be detected during respiratory infection with chemotype I yeast, suggesting that α-(1,3)-glucan could be produced during in vivo growth despite its absence in vitro. To directly test whether AGS1 contributes to chemotype I strain virulence, we prevented AGS1 function by RNA interference and by insertional mutation. Loss of AGS1 function in chemotype I does not impair the cytotoxicity of ags1(-) mutant yeast to cultured macrophages, nor does it affect the intracellular growth of yeast. In a murine model of histoplasmosis, the ags1(-) chemotype I mutant strains show no defect in lung infection or in extrapulmonary dissemination. Together, these studies demonstrate that AGS1 expression is dispensable for chemotype I yeast virulence, in contrast to the case for chemotype II yeast. Despite the absence of cell wall α-(1,3)-glucan, chemotype I yeast can avoid detection by Dectin-1 in a growth stage-dependent manner. This suggests the production of a unique Histoplasma chemotype I factor that, at least partially, circumvents the α-(1,3)-glucan requirement for yeast virulence.     

INFLUENCE OF THE QUINOLIZIDINE ALKALOID CONTENT OF LUPINUS ALBUS (FABACEAE) ON THE FEEDING CHOICE OF HELIX ASPERSA (GASTROPODA: PULMONATA)

Adult Helix aspersa snails were maintained individually forone week in plastic cages with 9 living Lupinus albus plantsas their only food. Among these 9 plants, 3 chemotypes bitter,intermediate and sweet which differed in their alkaloid contentwere equally represented. Each day, the leaf surface grazed and the number of leaves attackedby the snails were recorded for each chemotype and each snail.A consumption/ attack (C/A) ratio was calculated by dividing thesurface grazed (C) by the number of attacks (A). The numberof attacks and the grazed area were positively correlated foreach chemotype during the whole experiment, and the snails atesimilar quantities of lupin each day. After 4 and 6 days ofexperiment, we noticed a rejection of the bitter chemotype infavor of the intermediate and sweet ones respectively. Afterthe 6th day, the surface grazed per attack was significantlyhigher on the sweet chemotype than on the bitter plants. Wehypothesize that rejection of the bitter chemotype might berelated to (i) an alkaloids reaction threshold associated withan increase in the amount of alkaloids in the wounded plantsand/or (ii) aversive ingestive conditioning. (Received ; accepted 16 April 1999)     

Chemical and morphological diversity in wild populations of Mentha longifolia in Israel

Populations of Mentha longifolia, an endangered species in Israel, were tested for essential oil composition and conservational ability. In 2002-2003, 25 wild populations country-wide were tested, indicating population divergence into two chemotypes. Chemotype A was characterized by high levels of menthone and pulegone, and chemotype B by high levels of piperitenone oxide and piperitone oxide. Chemotype A was more abundant (22 of 25 populations) than chemotype B (11 of 25 populations). However, a chemotype/population interaction was not recorded (P?>?0.05). In spring 2003, seven of the 25 wild populations were resampled, propagated, and cultivated at the Newe Ya'ar campus. Then, in 2004, the propagated plants were tested for essential oil composition. The propagated plants maintained the essential oil composition as well as the chemotype-frequency distribution of the original wild population from which they were obtained. Since a chemotype/population interaction was not recorded, and the cultivated plants displayed the wild population essential oil composition, it can be concluded that i) the chemotype diversity is genetically based, and ii) the M. longifolia populations sampled can be horticulturally conserved.     

中国小麦赤霉病菌优势种——禾谷镰刀菌产毒素能力的研究

试验测定了分离自中国小麦赤霉病常发生地区病麦穗上的47个禾谷镰刀菌(Fusariumgraminearum)菌株的产毒紊能力。结果表明,它们可以产生25种包括单端孢霉烯族化合物(Trichothecenes)、倍半萜类化合物(sesquiterpenes)、赤霉烯酮(Zearalenone)和丁烯羟酸内酯(Butenolide)等类的已知次生代谢物。这些菌株属于化学型 I,其中,来自我国温暖麦区的菌株都属化学型IA (deoxynivalenol,3-acetyl),并在气候冷凉地区发现化学型IB(de-oxynivalenol,15-acetyl)菌株。     

Relations between the chemotype and the cell electrophoretic properties in Rhodobacter capsulatus strains

The cells of two Rhodobacter capsulatus strains, B10 and PG, and the LPS of their cell walls were studied by electrophysical and biochemical methods. Strain B10 was found to belong to the R chemotype, and strain PG, to the RS chemotype. A relation was revealed between the chemotype of the photosynthesizing bacteria Rhodobacter capsulatus and the electrophoretic properties of their cells.     

Monoterpenoid accumulation in 1,8-cineole,terpinolene and terpinen-4-ol chemotypes of Melaleuca alternifolia seedlings

Individual leaves of the three most common chemotypes of Melaleuca alternifolia were examined both quantitatively and qualitatively for volatile constituents from the emergence of the first true leaves, through to 6-week-old tenth leaf set material. The 1,8-cineole and terpinolene chemotypes were investigated and compared with the recently reported commercial terpinen-4-ol chemotype. The 1,8-cineole chemotype was found to accumulate 1,8-cineole and associated p-menthanes limonene, terpinen-4-ol and alpha-terpineol gradually with increasing leaf set number. As with the terpinen-4-ol variety, higher than expected concentrations of the pinenes and terpinolene were found only in the early leaf sets. The terpinolene variety showed two stages of terpinolene accumulation, the first at leaf sets 2-3 similar to the unexpected biosynthesis of terpinolene in the terpinen-4-ol chemotype and the second at leaf sets 8-9 which is characteristic of the terpinolene variety.     

Relations between the chemotype of <Emphasis Type="Italic">Rhodobacter capsulatus</Emphasis> strains and the cell electrophoretic properties

The cells of two Rhodobacter capsulatus strains, B10 and PG, and the LPS of their cell walls were studied by electrophysical and biochemical methods. Strain B10 was found to belong to the R chemotype, and strain PG, to the RS chemotype. A relation was revealed between the chemotype of the photosynthesizing bacteria Rhodobacter capsulatus and the electrophoretic properties of their cells.     

Variability in essential-oil composition of Piper marginatum sensu lato

This paper contains data on the chemical composition of the essential oils of 22 leaf samples of Piper marginatum Jacq. collected in different areas and ecosystems of the brazilian Amazon, as well as an overview of the available literature. The species presents a large synonymy based on their different leaf characteristics and distinct scents where some of them smell like anise or very close compounds. By GC, GC/MS, and cluster analysis, we identified seven chemotypes for the leaf oils. The main components found in chemotype I were safrole (1) and 3,4-(methylenedioxy)propiophenone (2). The chemotype II was dominated by 3,4-(methylenedioxy)propiophenone (2) and p-mentha-1(7),8-diene (10). The major compounds identified in chemotype III were 3,4-(methylenedioxy)propiophenone (2), myristicin (3), (E)-beta-ocimene (11), and gamma-terpinene (12). In the chemotype IV, the principal constituents were beta-caryophyllene (13), alpha-copaene (14), and 3,4-(methylenedioxy)propiophenone (2). The chemotype V was dominated by (E)-isoosmorhizole (6), (E)-anethole (8), and isoosmorhizole (7). The main compounds found in the chemotype VI were 2-methoxy-4,5-(methylenedioxy)propiophenone (4), methoxy-4,5-(methylenedioxy)propiophenone isomer 5, and (E)-isoosmorhizole (6). The major constituents in chemotype VII were beta-caryophyllene (13), bicyclogermacrene (15), and (E)-asarone (9).     

Bullatenone, 1,3-dione and sesquiterpene chemotypes of Lophomyrtus species

The only known natural source of the volatile bioactive compounds bullatenone 1 and 4-methyl-1-phenylpentane-1,3-dione 2 is the New Zealand endemic shrub Lophomyrtus bullata (Myrtaceae). GC and NMR analyses of essential oils and solvent extracts of L. bullata, L. obcordata and the hybrid L. "ralphii" showed several chemotypes, which did not correlate with species. Levels of 1 and 2 varied from dominant to low/undetectable and the most common chemotype was rich in allo-aromadendrene and other sesquiterpenes. The rare natural product E-4-methyl-1-phenyl-1-penten-3-one 4 was detected for the first time in this genus. The non-volatile cytotoxic compound bullataketal 5 co-occurred with bullatenone 1. An essential oil from the relatively rare bullatenone 1 chemotype showed antifungal activity against Candida albicans and Cladosporium resinae, and an oil from the 4-methyl-1-phenylpentane-1,3-dione 2 chemotype showed antibacterial activity against Bacillus subtilis.     

Host-plant choice and larval growth in the cinnabar moth: do pyrrolizidine alkaloids play a role?

Witte et al. (1992) described two distinct chemotypes of Senecio jacobaea L. Asteraceae, a chemotype with jacobine as one of the major pyrrolizidine alkaloids (PAs) and a chemotype with erucifoline as one of the major PAs. We hypothesized that the presence of erucifoline might be the factor responsible for the lack of success of the cinnabar moth on Senecio erucifolius L. Asteraceae and the S. jacobaea erucifoline chemotype. We performed a survey of the distribution of the two chemotypes in the Netherlands and compared this with the distribution map of Tyria jacobaeae L. Lepidoptera, Arctiidae. The distribution of the two chemotypes in the Netherlands is poorly correlated with the distribution of the cinnabar moth. The jacobine chemotype occurs along the coast and the erucifoline chemotype predominantly inward.An oviposition experiment showed that the cinnabar moth did not discriminate between the two chemotypes of S. jacobaea and S. erucifolius. Larval performance did not differ between the two chemotypes and species. Although the distribution of S. jacobaea jacobine chemotype is loosely associated with the abundance of the cinnabar moth the oviposition and growth experiments indicate that other factors than the presence of erucifoline play a role in this association.The absence of recordings of S. erucifolius as a foodplant for the cinnabar moth might be explained by the phenology of the foodplant. Ovipositing females of the univoltine cinnabar moth prefer flowering plants for oviposition. S. erucifolius starts flowering about 1–2 month later than S. jacobaea just after the peak density of moths.     

Annulation reaction enables the identification of an exocyclic amide tricyclic chemotype as retinoic acid Receptor-Related orphan receptor gamma (RORγ/RORc) inverse agonists

RORγt is the master regulator of the IL-23/IL-17 axis, a pathway that is clinically validated for the treatment of various immunological disorders. Over the last few years, our group has reported different chemotypes that potently act as inverse agonists of RORγt. One of them, the tricyclic pyrrolidine chemotype, has demonstrated biologic-like preclinical efficacy and has led to our clinical candidate BMS-986251. In this letter, we discuss the invention of an annulation reaction which enabled the synthesis of a tricyclic exocyclic amide chemotype and the identification of compounds with RORγt inverse agonist activity. Preliminary structure activity relationships are disclosed.     

Morphological heterogeneity among Salmonella lipopolysaccharide chemotypes in silver-stained polyacrylamide gels.

The morphological heterogeneity of lipopolysaccharides (LPSs) among salmonella mutants with different LPS chemotypes was analyzed in silver-stained polyacrylamide gels. The biochemical differences in the LPS chemotypes were reflected in the unique profiles of the purified LPSs. The LPS profiles in the whole-cell lysates were also unique for each chemotype. (Whole-cell lysates were assessed by a method which preferentially silver stains LPS and by a proteinase K digest of whole-cell lysates. The silver-stained LPS profiles of proteinase K-digested lysates were similar to the homologous purified LPS and could be used to preliminarily characterize the LPS chemotype before purification.) In summary, biochemical variation in LPS composition can be detected in silver-stained polyacrylamide gels.     

The sensitivity of smooth and rough mutants ofSalmonella typhimurium to bactericidal and bacteriolytic action of serum,lysozyme and to phagocytosis

The sensitivity of smooth and rough mutants ofSalmonella typhimurium belonging to different chemotypes to bactericidal and bacteriolytic action of antibodies, complement and lysozyme was investigated. By the action of specific antibodies and complement the majority of strains was killed and in the presence of sufficient amount of lysozyme even lysed. Sera of newborn piglet which do not contain antibodies however, were able to kill regularly only strains of lower chemotypes (Rc and Rb). Smooth strains were usually resistant to the action of piglet serum whereas strains of Ra chemotype were killed only by sera of some piglets. Using the liver clearance method a significant correlation between the lipopolysaccharide chemotype of the particular strain and the degree of phagocytosis was found.     

Protective action of a vaccine made from Salmonella minnesota R 595 in the intranasal infection of mice with P. aeruginosa

The comparative study of heated corpuscular vaccines prepared from S. minnesota mutant R 595, chemotype Re, from S. minnesota strain SF 1111 with defective lipopolysaccharide and from P. aeruginosa strain PA 103 has been carried out. The vaccine prepared from the chemotype Re mutant, in contrast to the vaccine prepared from S. minnesota strain SF 1111, has been found to induce the development of active immunity (and the corresponding antiserum, passive immunity) to P. aeruginosa introduced intranasally into mice, as well as to stimulate the elimination of the cells of P. aeruginosa infective strain from the lungs of the mice. The potency of the vaccine prepared from the chemotype Re mutant has been found to be significantly no different from that of the vaccine prepared from P. aeruginosa strain PA 103.     

Immunochemical characterization and taxonomic evaluation of the O polysaccharides of the lipopolysaccharides of Pseudomonas syringae serogroup O1 strains

The O polysaccharide (OPS) of the lipopolysaccharide (LPS) of Pseudomonas syringae pv. atrofaciens IMV 7836 and some other strains that are classified in serogroup O1 was shown to be a novel linear alpha-D-rhamnan with the tetrasaccharide O repeat -->3)-alpha-D-Rhap-(1-->3)-alpha-D-Rhap-(1-->2)-alpha-D-R hap-(1-->2)- alpha-D-Rhap-(1--> (chemotype 1A). The same alpha-D-rhamnan serves as the backbone in branched OPSs with lateral (alpha1-->3)-linked D-Rhap, (beta1-->4)-linked D-GlcpNAc, and (alpha1-->4)-linked D-Fucf residues (chemotypes 1B, 1C, and 1D, respectively). Strains of chemotype 1C demonstrated variations resulting in a decrease of the degree of substitution of the backbone 1A with the lateral D-GlcNAc residue (chemotype 1C-1A), which may be described as branched regular left arrow over right arrow branched irregular --> linear OPS structure alterations (1Cleft arrow over right arrow 1C-1A --> 1A). Based on serological data, chemotype 1D was suggested to undergo a 1D left arrow over right arrow 1D-1A alteration, whereas chemotype 1B showed no alteration. A number of OPS backbone-specific monoclonal antibodies (MAbs), Ps(1-2)a, Ps(1-2)a(1), Ps1a, Ps1a(1), and Ps1a(2), as well as MAbs Ps1b, Ps1c, Ps1c(1), Ps1d, Ps(1-2)d, and Ps(1-2)d(1) specific to epitopes related to the lateral sugar substituents of the OPSs, were produced against P. syringae serogroup O1 strains. By using MAbs, some specific epitopes were inferred, serogroup O1 strains were serotyped in more detail, and thus, the serological classification scheme of P. syringae was improved. Screening with MAbs of about 800 strains representing all 56 known P. syringae pathovars showed that the strains classified in serogroup O1 were found among 15 pathovars and the strains with the linear OPSs of chemotype 1A were found among 9 of the 15 pathovars. A possible role for the LPS of P. syringae and related pseudomonads as a phylogenetic marker is discussed.     

Chemical variation in the leaf essential oil of Melaleuca quinquenervia (Cav.) S.T. Blake

An examination of the leaf oils of Melaleuca quinquenervia over its geographical range in Australia and Papua New Guinea has shown wide variation in chemical composition but only two major chemotypes. Chemotype 1 is comprised of E-nerolidol (74–95%) and linalool (14–30%) and is found from Sydney, north along the east coast of Australia to Selection Flat, New South Wales, with an isolated occurrence near Maryborough, Queensland. Two divisions occur in this chemotype which are based on the presence or absence of significant proportions of linalool (14–40%). Chemotype 2 contains 1,8-cineole (10–75%), viridiflorol (13–66%), α-terpineol (0.5–14%) and β-caryophyllene (0.5–28%) in varying proportions and order of dominance in the oils. It is found throughout the distribution of the species, from Sydney to Papua New Guinea and New Caledonia. Within chemotype 2 there appears to be a continuous spread of oil composition without formation of any further discrete divisions as in chemotype 1.Analyses have shown that M. quinquenervia trees that occur at latitudes south of 25°S have high oil yields (1–3% w/w%, fresh leaves) and comprise chemotypes 1 and 2. North of 25°S, however, chemotype 1 does not occur and oil yields amongst the Australian populations are uniformly low (0.1–0.2%).     

Variation in pyrrolizidine alkaloid patterns of Senecio jacobaea

We studied the variation in pyrrolizidine alkaloid (PA) patterns of lab-grown vegetative plants of 11 European Senecio jacobaea populations. Plants were classified as jacobine, erucifoline, mixed or senecionine chemotypes based on presence and absence of the PAs jacobine or erucifoline. Due to the presence of jacobine, total PA concentration in jacobine chemotypes was higher than in erucifoline chemotypes. Both relative and absolute concentrations of individual PAs differed between half-sib and clonal families, which showed that variation in PA patterns had a genetic basis. Within most populations relative abundance of PAs varied considerably between individual plants. Most populations consisted either of the jacobine chemotype or of the erucifoline chemotype, sometimes in combination with mixed or senecionine chemotypes.