(22<Emphasis Type="Italic">R</Emphasis>,23<Emphasis Type="Italic">R</Emphasis>)-3β-hydroxy-22,23-epoxy-5α-ergost-8(14)-en-15-one: Improved synthesis and toxicity to MCF-7 cells

The chemical synthesis of (22R,23R)-3β-hydroxy-22,23-epoxy-5α-ergost-8(14)-en-15-one from (22A)-3β-acetoxy-5α-ergosta-7,14,22-triene was improved. The stages of obtaining and isomerization of (22A)-3β-acetoxy-14α15α-epoxy-5α-ergosta-7,22-diene were optimized. The introduction of (22R,23R)-epoxide cycle was carried out by alkaline treatment of intermediate (22S,23R)-3β,23-diacetoxy-22-iodo-5α-ergost-8(14)-en-15-one. In cells of human breast carcinoma MCF-7, (22R,23R)-3β-hydroxy-22,23-epoxy-5α-ergost-8(14)-en-15-one showed a high toxicity (TC₅₀ = 0.4±0.1 μM at 48-h incubation in serum-free medium).     

In vitro and in vivo studies of functional activity of new low molecular weight agonists of the luteinizing hormone receptor

The use of luteinizing hormone (LH) and its structural and functional homolog human chorionic gonadotropin (hCG) leads to hyperstimulation of LH-dependent signalling pathways and to desensitization of LH receptors. Therefore, the development of low molecular weight agonists of the LH receptor without these disadvantages has been carried out in recent years. These agonists, unlike gonadotropins, are active when administered orally. The greatest prospects are associated with the development of the thienopyrimidine derivatives structurally similar to compound Org 43553. The purpose of this work was the synthesis of new thienopyrimidine derivatives TP03 and TP04, the study of the regulation of LH-sensitive adenylyl cyclase signalling system in rat testes, and the evaluation of the ability of TP03 and TP04 to stimulate testosterone synthesis in male rats at different routes of administration. In the concentration range 10^–7–10^–3 M, TP03 and TP04 induced an increase of the basal adenylyl cyclase (AC) activity in rat testicular membranes with the EC₅₀ values of 390 and 759 nM, respectively. At a concentration of 10^–4 M, AC-stimulating effects of TP03 and TP04 were 213 and 122%, respectively, which indicates a higher activity of TP03 under in vitro conditions. At the same time, the AC-stimulating effect of TP03 was approximately 2.5-fold weaker than that of hCG (10^–8 M). Upon simultaneous administration of hCG and thienopyrimidine derivatives, their stimulating effects on the AC activity were additive due to the different localization of their binding sites in the LH receptor. Compound TP03 (25 mg/kg), when administered intraperitoneally to male rats, was more efficient than TP04: the maximal increase in the testosterone level (3 h after administration) was by 60% higher than that induced by TP04. TP03 increased the testosterone level after oral administration (50 mg/kg) as well, but the effect was weaker than in the case of the intraperitoneal injection. Orally administered TP04 exhibited a low activity. The results suggest that 5-amino-N-tert-butyl-2-(methylsulfonyl)-4-(3-(nicotinamide)phenyl) thieno[2,3-d]pyrimidine-6-carboxamide (TP03) can be used for the development of the drugs that stimulate steroidogenesis in Leydig cells.     

Karyotypic study of five Lutjanid species using conventional and Ag-NORs banding techniques

The first cytogenetic comparisons of five snapper species from Thailand were presented here. Renal cell samples were taken from blacktail snapper (Lutjanus fulvus), five lined snapper (L. quinquelineatus), dory snapper (L. fulviflamma), brownstripe red snapper (L. vitta), and mangrove red snapper (L. argentimaculatus). The mitotic chromosome preparation was prepared directly from kidney cells. Conventional staining and Ag-NOR banding techniques were applied to stain the chromosomes. The results exhibited that all five snapper species have the diploid chromosome numbers of 2n = 48 and the fundamental numbers (NF) of 48. The presences of large, medium, and small telocentric chromosomes were 22-24-2, 24-20-4, 36-10-2, 28-16-4 and 36-10-2, respectively. The Ag- NORs banding technique provides the pair of nucleolar organizer regions (NORs) at subcentromeric region of the long arm of the respective telocentric chromosome pairs 9, 1, 3, 4 and 9. Their karyotype formulas is as follows: L. fulvus (2n = 48): L ₂₂ ^t + M ₂₄ ^t + S ₂ ^t , L. quinquelineatus (2n = 48): L ₂₄ ^t + M ₂₀ ^t + S ₄ ^t , L. fulviflamma (2n = 48): Lt36 + Mt10 + St2, L. vitta (2n = 48): L ₂₈ ^t + M ₁₆ ^t + S ₄ ^t , and L. argentimaculatus (2n = 48): L ₃₆ ^t + M ₁₀ ^t + S ₂ ^t .     

Molecular mapping of a new temperature-sensitive gene <Emphasis Type="Italic">LrZH22</Emphasis> for leaf rust resistance in Chinese wheat cultivar Zhoumai 22

Leaf rust, caused by Puccinia triticina, is one of the most widespread diseases in common wheat globally. The Chinese wheat cultivar Zhoumai 22 is highly resistant to leaf rust at the seedling and adult stages. Seedlings of Zhoumai 22 and 36 lines with known leaf rust resistance genes were inoculated with 13 P. triticina races for gene postulation. The leaf rust response of Zhoumai 22 was different from those of the single gene lines. With the objective of identifying and mapping, the new gene(s) for resistance to leaf rust, F₁, F₂ plants and F_2:3 lines from the cross Zhoumai 22/Chinese Spring were inoculated with Chinese P. triticina race FHDQ at the seedling stage. A single dominant gene, tentatively designated LrZH22, conferred resistance. To identify other possible genes in Zhoumai 22, ten P. triticina races avirulent on Zhoumai 22 were used to inoculate 24 F_2:3 lines. The same gene conferred resistance to all ten avirulent races. A total of 1300 simple sequence repeat (SSR) markers and 36 EST markers on 2BS were used to test the parents, and resistant and susceptible bulks. Resistance gene LrZH22 was mapped in the chromosome bin 2BS1-0.53-0.75 and closely linked to six SSR markers (barc183, barc55, gwm148, gwm410, gwm374 and wmc474) and two EST markers (BF202681 and BE499478) on chromosome arm 2BS. The two closest flanking SSR loci were Xbarc55 and Xgwm374 with genetic distances of 2.4 and 4.8 cM from LrZH22, respectively. Six designated genes (Lr13, Lr16, Lr23, Lr35, Lr48 and Lr73) are located on chromosome arm 2BS. In seedling tests, LrZH22 was temperature sensitive, conferring resistance at high temperatures. The reaction pattern of Zhoumai 22 was different from that of RL 4031 (Lr13), RL 6005 (Lr16) and RL 6012 (Lr23), Lr35 and Lr48 are adult-plant resistance genes, and Lr73 is not sensitive to the temperature. Therefore, LrZH22 is likely to be a new leaf rust resistance gene or allele.     

Intestinal enterobacteria of the hibernating <Emphasis Type="Italic">Apis mellifera mellifera</Emphasis> L. bees

Dynamics of enterobacteria of normal intestinal microflora was studied in Apis mellifera mellifera L. bees hibernating under snow in the Western Urals. The cell numbers (N) of the predominant species Klebsiella oxytoca increased from 10-10⁶ CFU/bee in November 2004 to 10⁴-10⁷ CFU/bee in March 2005; its frequency of occurrence (P) increased from 92 to 100%. Increase of Providencia rettgeri (11.2004: N up to 10⁶, P 25%; 03.2005: N 10²-10⁶, P 80%) was accompanied by the substitution of Morganella morganii (11.2004: N up to 10⁶, P 25%) with Proteus vulgaris (03.2005: N up to 10⁵, P 8%). By spring, Hafnia alvei and Citrobacter sp., which are pathogenic to bees, disappeared (11.2004: N up to 10⁵, P 13 and 10%, respectively). Endophytic species Pantoea agglomerans, Leclecria sp., and other representatives of the “Enterobacter agglomerans” group were present in November and after the first emergence in spring (N up to 10⁵; November: P 15%; April: P 23%). In April, the number of enterobacteria decreased to 10⁵, and P. rettgeri became the predominant species (P 54%) instead of K. oxytoca (P 43%).     

Anti-Müllerian hormone may regulate the number of calbindin-positive neurons in the sexually dimorphic nucleus of the preoptic area of male mice

Background

The male brain is putatively organised early in development by testosterone, with the sexually dimorphic nucleus of the medial preoptic area (SDN) a main exemplifier of this. However, pubescent neurogenesis occurs in the rat SDN, and the immature testes secrete anti-Müllerian hormone (AMH) as well as testosterone. We have therefore re-examined the development of the murine SDN to determine whether it is influenced by AMH and/or whether the number of calbindin-positive (calbindin^+ve) neurons in it changes after pre-pubescent development.

Methods

In mice, the SDN nucleus is defined by calbindin^+ve neurons (CALB-SDN). The number and size of the neurons in the CALB-SDN of male and female AMH null mutant (Amh ^-/- ) mice and their wild-type littermates (Amh ^+/+ ) were studied using stereological techniques. Groups of mice were examined immediately before the onset of puberty (20 days postnatal) and at adulthood (129–147 days old).

Results

The wild-type pre-pubertal male mice had 47% more calbindin^+ve neurons in the CALB-SDN than their female wild-type littermates. This sex difference was entirely absent in Amh ^-/- mice. In adults, the extent of sexual dimorphism almost doubled due to a net reduction in the number and size of calbindin^+ve neurons in females and a net increase in neuron number in males. These changes occurred to a similar extent in the Amh ^-/- and Amh ^+/+ mice. Consequently, the number of calbindin^+ve neurons in Amh ^-/- adult male mice was intermediate between Amh ^+/+ males and Amh ^+/+ females. The sex difference in the size of the neurons was predominantly generated by a female-specific atrophy after 20 days, independent of AMH.

Conclusions

The establishment of dimorphic cell number in the CALB-SDN of mice is biphasic, with each phase being subject to different regulation. The second phase of dimorphism is not dependent on the first phase having occurred as it was present in the Amh ^-/- male mice that have female-like numbers of calbindin^+ve neurons at 20 days. These observations extend emerging evidence that the organisation of highly dimorphic neuronal networks changes during puberty or afterwards. They also raise the possibility that cellular events attributed to the imprinting effects of testosterone are mediated by AMH.

     

Substituted 16α,17α-cyclohexanopregnanes: the anionic oxy-Cope rearrangement of 3β-<Emphasis Type="Italic">tert</Emphasis>-butyldimethylsilyloxy-19-hydroxy-19-vinyl-16α,17α-cyclohexapregn-5-en-20-one

(19R)-and (19S)-tert-Butyldimethylsilyl (TBS) ethers of 19-hydroxy-19-vinyl-16α,17α-cyclohexanopregn-5-en-20-ones were synthesized. These compounds containing the 1,5-oxydienoic motif were subjectedto the anionic oxy-Cope rearrangement to obtain 3β-TBS ether of 6β-(3-oxopropyl)-16α,17α-cyclohexano-19-norpregn-5(10)-en-20-one. The structures of the compounds synthesized were confirmed by the analysis of their ¹H and ¹³C NMR spectra.     

The combined effects of blue light and dilution rate on lipid class and fatty acid composition of <Emphasis Type="Italic">Tisochrysis lutea</Emphasis>

The lipid class and the fatty acid compositions of microalgae highly influence bivalve larval and post-larval development. Light is an essential environmental factor for microalgal culture, and quantity and quality of light may induce changes in the biochemical composition of the algae. The objective of this study was to investigate the effect of light spectrum (blue vs. white light) on lipid class and fatty acid compositions of Tisochrysis lutea cultured in a chemostat. Two different dilution rates (D) were assayed for each light spectrum: 0.2 and 0.7 day^?1. Triacylglycerol (TAG), sterol, and hydrocarbon (HC) content increased sharply at low D. The proportion of alkenones was significantly reduced under blue light. Polyunsaturated fatty acids (PUFA), and particularly n-3 PUFA, content in phospholipids (PL) increased under blue light compared to white light at low D. Thus, blue light raised 22:6(n-3) levels in total lipids of T. lutea at low D. The cultivation of T. lutea in a chemostat at low D under blue light may improve nutritional value as feed for bivalve larvae by modifying the PUFA profile, especially increasing 22:6(n-3).     

Antifungal activity of 3-acetylbenzamide produced by actinomycete WA23-4-4 from the intestinal tract of <Emphasis Type="Italic">Periplaneta americana</Emphasis>

Actinomycetes are well-known for producing numerous bioactive secondary metabolites. In this study, primary screening by antifungal activity assay found one actinomycete strain WA23-4-4 isolated from the intestinal tract of Periplaneta americana that exhibited broad spectrum antifungal activity. 16S rDNA gene analysis of strain WA23-4-4 revealed close similarity to Streptomyces nogalater (AB045886) with 86.6% sequence similarity. Strain WA23-4-4 was considered as a novel Streptomyces and the 16s rDNA sequence has been submitted to GenBank (accession no. KX291006). The maximum antifungal activity of WA23-4-4 was achieved when culture conditions were optimized to pH 8.0, with 12% inoculum concentration and 210 ml ISP2 medium, which remained stable between the 5^th and the 9^th day. 3-Acetyl benzoyl amide was isolated by ethyl acetate extraction of WA23-4-4 fermentation broth, and its molecular formula was determined as C₉H₉NO₂ based on MS, IR, ¹H, and ¹³C NMR analyses. The compound showed significant antifungal activity against Candida albicans ATCC 10231 (MIC: 31.25 μg/ml) and Aspergillus niger ATCC 16404 (MIC: 31.25 μg/ml). However, the compound had higher MIC values against Trichophyton rubrum ATCC 60836 (MIC: 500 μg/ml) and Aspergillus fumigatus ATCC 96918 (MIC: 1,000 μg/ml). SEM analysis showed damage to the cell membrane of Candida albicans ATCC 10231 and to the mycelium of Aspergillus niger ATCC 16404 after being treatment with 3-acetyl benzoyl amide. In conclusion, this is the first time that 3-acetyl benzoyl amide has been identified from an actinomycete and this compound exhibited antifungal activity against Candida albicans ATCC 10231 and Aspergillus niger ATCC 16404.     

Steroid Compounds from Far Eastern Starfishes <Emphasis Type="Italic">Henricia aspera</Emphasis> and <Emphasis Type="Italic">H. tumida</Emphasis>

Six new natural compounds were isolated from two Far Eastern starfish species, Henricia aspera and H. tumida, collected in the Sea of Okhotsk. Two new glycosylated steroid polyols were obtained from H. aspera: asperoside A and asperoside B, which were shown to be (20R,24R, 25S)-3-O-(2,3-di-O-methyl-β -D-xylopyranosyl)-24-methyl-5α-cholest-4-ene-3β, 6β,8,15α,16β,26-hexaol and (20R, 24R,25S,22E)-3-O-(2,4-di-O-methyl-β-D-xylopyranosyl)-24-methyl-5α-cholest-22-ene-3β,4β,6β,8,15α,26-hexaol, respectively. Two other glycosylated polyols, tumidoside A, with the structure elucidated as (20R, 22E)-3-O-(2,4-di-O-methyl-β -D-xylopyranosyl)-26,27-dinor-24-methyl-5α-cholest-22-ene-3β,4β,6β,8,15α,25-hexaol, and tumidoside B, whose structure was elucidated as (20R,24S)-3-O-(2,3-di-O-methyl-β-D-xylopyranosyl)-5α-cholestan-3β,4β,6β,8,15α,24-hexaol, were isolated from the two starfish species. (20R, 24S)-5α-Cholestan-3β,6β,15α,24-tetraol and (20R, 24S)-5α-cholestan-3β,6β,8,15α,24-pentaol were identified only in H. tumida. The known monoglycosides henricioside H1 and laeviuscolosides H and G were also identified in both species.     

Theoretical study of the H + HCN → H + HNC process

We present a theoretical study on the detailed mechanism and kinetics of the H+HCN →H+HNC process. The potential energy surface was calculated at the complete basis set quantum chemical method, CBS-QB3. The vibrational frequencies and geometries for four isomers (H₂CN, cis-HCNH, trans-HCNH, CNH₂), and seven saddle points (TSn where n = 1 ? 7) are very important and must be considered during the process of formation of the HNC in the reaction were calculated at the B3LYP/6-311G(2d,d,p) level, within CBS-QB3 method. Three different pathways (PW1, PW2, and PW3) were analyzed and the results from the potential energy surface calculations were used to solve the master equation. The results were employed to calculate the thermal rate constant and pathways branching ratio of the title reaction over the temperature range of 300 up to 3000 K. The rate constants for reaction H + HCN → H + HNC were fitted by the modified Arrhenius expressions. Our calculations indicate that the formation of the HNC preferentially occurs via formation of cis–HCNH, the fitted expression is k _{P W2}(T) = 9.98 × 10^?22 T ^2.41 exp(?7.62 kcal.mol^?1/R T) while the predicted overall rate constant k _{O v e r a l l} (T) = 9.45 × 10^?21 T ^2.15 exp(?8.56 kcal.mol^?1/R T) in cm ³ molecule ^?1 s ^?1.

Open image in new window

Graphical Abstract (a) Potential energy surface, (b) thermal rate constants as a function of temperature and (c) the branching ratios (%) of PW1, PW2, PW3 pathways involved in rm H + HCN → H + HNC process.

     

New data on chromosomes of parasitic wasps of the subfamily Ichneumoninae (Hymenoptera,Ichneumonidae)

The new data on chromosomes of parasitic wasps of the subfamily Ichneumoninae: Centeterus major (2n = 22), Diadromus troglodytes (2n = 22), D. varicolor (2n = 22), Tycherus infimus (2n = 22), Cratichneumon rufifrons (2n = 26), Eristicus clarigator (2n =.26), and Ctenichneumon funereus (2n = 16) were obtained. Some aspects of the chromosomal variability of Ichneumoninae are discussed.     

Antimicrobial activities of some novel thiazoles

2-(4-Phenylthiazol-2(3H)-ylidene)-malononitrile was synthesized by treating 1-phenyl-2-thiocyanatoethanone with malononitrile. Reaction of 2-(4-phenylthiazol-2(3H)-ylidene)-malononitrile with hydrazine hydrate afforded 4-(4-phenylthiazol-2-yl)-1H-pyrazole-3,5-diamine, reaction with benzylidenemalononitrile yielded 2-(5-benzylidene-4-phenyl-5H-thiazol-2-ylidene)-malononitrile, and coupling with benzenediazonium chloride gave 2-(4-phenyl-5-phenylazo-3H-thiazol-2-ylidene)-malononitrile. Diaminopyrazole reacted with enaminonitrile to yield the 3-(4-phenylthiazol-2-yl)pyrazolo[1,5-a]pyrimidine-2,7-diamine. All synthesized compounds showed significant antimicrobial activities with MIC range of 5–750 µg/mL. The results demonstrated a correlation of the hydrophobicity of the compounds with their antimicrobial activity. The most potent antimicrobial compound was 2-(4-phenylthiazol-2(3H)-ylidene)-malononitrile.     

Overexpression of cytochrome p450 125 in <Emphasis Type="Italic">Mycobacterium</Emphasis>: a rational strategy in the promotion of phytosterol biotransformation

Androst-4-ene-3, 17-dione (AD) and androst-1, 4-diene-3, 17-dione (ADD) are generally produced by the biotransformation of phytosterols in Mycobacterium. The AD (D) production increases when the strain has high NAD⁺/NADH ratio. To enhance the AD (D) production in Mycobacterium neoaurum TCCC 11978 (MNR M3), a rational strategy was developed through overexpression of a gene involved in the phytosterol degradation pathway; NAD⁺ was generated as well. Proteomic analysis of MNR cultured with and without phytosterols showed that the steroid C27-monooxygenase (Cyp125-3), which performs sequential oxidations of the sterol side chain at the C27 position and has the oxidative cofactor of NAD⁺ generated, played an important role in the phytosterol biotransformation process of MNR M3. To improve the productivity of AD (D), the cyp125-3 gene was overexpressed in MNR M3. The specific activity of Cyp125-3 in the recombinant strain MNR M3C3 was improved by 22% than that in MNR M3. The NAD⁺/NADH ratio in MNR M3C3 was 131% higher than that in the parent strain. During phytosterol biotransformation, the conversion of sterols increased from 84 to 96%, and the yield of AD (D) by MNR M3C3 was increased by approximately 18% for 96 h fermentation. This rational strain modification strategy may also be applied to develop strains with important application values for efficient production of cofactor-dependent metabolites.     

Role of Kisspeptin and Leptin in the Development of Immune Reactivity during Pregnancy

The effects of kisspeptin, an important regulator of reproductive function, and leptin, a classical metabolic hormone, on the formation of inducible regulatory T cells (iTreg) and T helper cells that produce interleukin 17 (Th17), as well as on the activity of indoleamine 2,3-dioxygenase (IDO) have been studied. Both hormones are actively produced by the placenta and involved in the formation of a new hormonal profile during pregnancy. It was found that kisspeptin at concentrations typical for trimesters I–III of pregnancy stimulates the formation of iTreg and simultaneously inhibit Th17 induction. Regardless of the used concentration, kisspeptin increases the secretion of interleukin-10 (IL-10) and reduces the production of IL-17A in CD4⁺ T lymphocytes in women. At the same time leptin at physiological concentrations typical for pregnancy has the opposite effect, inhibiting the formation of iTreg without affecting the production of IL-10 in cultures of CD4⁺T lymphocytes and simultaneous stimulating the induction of Th17 and production of IL-17A in CD4⁺T lymphocytes. At the concentration corresponding to trimesters II–III of pregnancy both hormones significantly enhance lipopolysaccharide-induced activity of IDO in monocytes.     

Association of three single nucleotide polymorphisms at the SIX1-SIX6 locus with primary open angle glaucoma in the Chinese population

This study investigated the genetic association of three single nucleotide polymorphisms(SNPs; rs10483727, rs33912345, and rs146737847) at the SIX1-SIX6 locus with primary open angle glaucoma(POAG) in the Chinese population. A total of 866 subjects with POAG(685 high-tension glaucoma(HTG) and 181 normal-tension glaucoma(NTG)) and 266 control individuals were included. Significant genetic association was identified for rs10483727 in HTG(P=0.02; odds ratio(OR)=1.31), NTG(P=7.41×10~(-6); OR=2.71), and POAG(i.e., HTG and NTG combined; P=0.001; OR=1.44). rs33912345 was also significantly associated with HTG(P=0.008; OR=1.36), NTG(P=2.72×10~(-6); OR=2.27), and POAG(P=3.84×10~(-4); OR=1.49). The rare SIX6 mutation, rs146737847, was not found in the subjects enrolled in this study. Stratification by patient age identified that both rs10483727 and rs33912345 were significantly associated with NTG in patients aged above 40 years(P=2.08×10~(-5); OR=2.28), whereas in patients aged between 20–40 years, rs33912345 was significantly associated with NTG(P=0.017; OR=2.06). In HTG, the genetic associations for both rs10483727 and rs33912345 were significant in patients aged between 20–40 years(P=0.006; OR=1.56) but not in those aged above 40 years(P=0.118, OR=1.21 and P=0.042, OR=1.29, respectively). This study replicated the association of POAG with two SNPs at the SIX1-SIX6 locus and demonstrated that SNPs, rs10483727 and rs33912345, are significantly associated with POAG, especially with NTG in patients aged above 40 years.     

The effect of genetic environment on locus-specific instability of the <Emphasis Type="Italic">yellow</Emphasis> gene in the Uman’ population of <Emphasis Type="Italic">Drosophila melanogaster</Emphasis>

The effects of genotype of the laboratory strains, C(1)DX, ywf/Y, 23.5 MRF/CyL ⁴, and C(1)DX,yf; π₂, on locus-specific instability in the yellow gene of the strains y ^2-217, y ^2-715, and y ^2-700 from Uman’ population of Drosophila melanogaster was studied. Crosses of the males from Uman’-derived lines with the C(1)DX,ywf/Y females yielded a cascade of derivatives, mostly consisting of y ⁺ and y ² alleles, while their crosses with the 23.5 MRF/CyL ⁴ and C(1)DX,yf; π₂ females mostly resulted in the appearance of y ⁺ and y ¹ derivatives. The genomes of laboratory strains used in the study contained the full-sized hobo elements, which could differ from one another relative to the structure of variable region and affinity to different DNA sequences.     

Genetic diversity near the <Emphasis Type="Italic">DGAT1-2</Emphasis> gene for high oleic acid content and kernel trait variation in a maize breeding collection

Previous studies in maize have identified three quantitative trait loci (QTLs) coding for high oleic acid content (HOAC) (QTLs oleic6-1, oleic6-2, and oleic6-3) at bins 6.04–6.05, proximal to the DGAT1-2 gene. The aims of this work were (i) to discover new markers for linkage disequilibrium (LD) and haplotype analysis distal to DGAT1-2, (ii) to develop a new DGAT1-2 PCR probe to detect the allele determining HOAC (F469 insertion), (iii) to conduct cluster analysis for kernel traits, and (iv) to assess genetic diversity, LD, and association analysis for kernel traits with the DGAT1-2 PCR probe and 13 markers previously mapped near DGAT1-2 in the Argentine temperate maize collection of 111 inbred lines. The results showed high haplotype diversity distal to DGAT1-2 and relatedness between the inbred line LP199 (with HOAC) and the Non-Stiff Stalk line W22 (reference genome). The frequency of F469 was low (20%). F469 was clustered with flint-grain type characteristics, whereas HOAC was associated with F469 across linear models. Genetic diversity at bins 6.04–6.05 was high (0.62), whereas LD extent was low (r²?≤?0.45). This low extent of LD indicates a high level of recombination and no LD between DGAT1-2 and markers flanking QTLs oleic6-1 to 3. Nevertheless, the significant LD between markers flanking those QTLs and the cosegregation of F469 with nc009 (markers flanking QTLs oleic6-1 and 2) during inbred line conversion suggest that these QTLs might contribute to HOAC in the breeding collection. However, further studies are needed to precise mapping at bins 6.04–6.05 for breeding purposes.     

Cell wall glycopolymers of type strains from three species of the genus <Emphasis Type="Italic">Actinoplanes</Emphasis>

The structures of cell wall glycopolymers from the type strains of three Actinoplanes species were investigated using chemical methods, NMR spectroscopy, and mass spectrometry. Actinoplanes digitatis VKM Ac-649^T contains two phosphate-containing glycopolymers: poly(diglycosyl-1-phosphate) →6)-α-D-GlcpNAc-(1-P-6)-α-D-GlcpN-(1→ and teichoic acid →1)-sn-Gro-(3-P-3)-β-[β-D-GlcpNAc-(1→2]-D-Galp-(1→. Two glycopolymers were identified in A. auranticolor VKM Ac-648^T and A. cyaneus VKM Ac-1095^T: minor polymer–unsubstituted 2,3-poly(glycerol phosphate), widely abundant in actinobacteria (Ac-648^T), and mannan with trisaccharide repeating unit →2)-α-D-Manp-(1→2)-α-D-Manp(1→6)-α-D-Manp-(1→(Ac-1095^T). In addition, both microorganisms contain a teichuronic acid of unique structure containing a pentasaccharide repeating unit with two residues of glucopyranose and three residues of diaminouronic acids in D-manno- and/or D-gluco-configuration. Each of the strains demonstrates peculiarities in the structure of teichuronic acid with respect to the ratio of diaminouronic acids and availability and location of O-methyl groups in glucopyranose residues. All investigated strains contain a unique set of glycopolymers in their cell walls with structures not described earlier for prokaryotes.