Volatile Composition Screening of Salix spp. Nectar Honey: Benzenecarboxylic Acids,Norisoprenoids, Terpenes,and Others

Salix spp. nectar honey volatiles of Croatian origin were analyzed by headspace solid‐phase microextraction (HS‐SPME) and ultrasonic solvent extraction (USE), followed by gas chromatography and mass spectrometry (GC, GC/MS). Isolated volatiles were found in the honey headspace and extracts with almost exclusive distribution of several abundant compounds (e.g., phenylacetic acid, pinocembrin, 8‐hydroxy‐4,7‐dimethylcoumarin, and 3‐hydroxy‐trans‐β‐damascone in the extracts, or safranal and lilac alcohols in the headspace). Comparison with Croatian Salix spp. honeydew honey revealed similarities regarding distribution of important shikimate pathway derivatives (e.g., high percentage of phenylacetic acid) and several norisoprenoids (α‐isophorone and 4‐oxoisophorone). On the other hand, distinct features of this honey were occurrence of compounds such as pinocembrin, 8‐hydroxy‐4,7‐dimethylcoumarin, phenylacetonitrile, norisoprenoids (major ones: 3‐hydroxy‐trans‐β‐damascenone and trans‐β‐damascone), more pronounced variability of linalool‐derived compounds, as well as the abundance of 3‐methylpropanoic acid, 3‐methylbutanoic acid, 2‐methylpentanoic acid, and 3‐methylpentan‐1‐ol.     

Comprehensive Study of Mediterranean (Croatian) Propolis Peculiarity: Headspace,Volatiles, Anti‐Varroa‐Treatment Residue,Phenolics, and Antioxidant Properties

Eight propolis samples from Croatia were analyzed in detail, to study the headspace, volatiles, anti‐Varroa‐treatment residue, phenolics, and antioxidant properties. The samples exhibited high qualitative/quantitative variability of the chemical profiles, total phenolic content (1,589.3–14,398.3 mg GAE (gallic acid equivalent)/l EtOH extract), and antioxidant activity (11.1–133.5 mmol Fe²⁺/l extract and 6.2–65.3 mmol TEAC (Trolox^® equivalent antioxidant capacity)/l extract). The main phenolics quantified by HPLC‐DAD at 280 and 360 nm were vanillin, p‐coumaric acid, ferulic acid, chrysin, galangin, and caffeic acid phenethyl ester. The major compounds identified by headspace solid‐phase microextraction (HS‐SPME), simultaneous distillation extraction (SDE), and subsequent GC‐FID and GC/MS analyses were α‐eudesmol (up to 19.9%), β‐eudesmol (up to 12.6%), γ‐eudesmol (up to 10.5%), benzyl benzoate (up to 28.5%), and 4‐vinyl‐2‐methoxyphenol (up to 18.1%). Vanillin was determined as minor constituent by SDE/GC‐FID/MS and HPLC‐DAD. The identified acaricide residue thymol was ca. three times more abundant by HS‐SPME/GC‐FID/MS than by SDE/GC‐FID/MS and was not detected by HPLC‐DAD.     

Four New Steroidal Glycosides,Protolinckiosides A – D,from the Starfish Protoreaster lincki

Four new steroidal glycosides, protolinckiosides A – D ( 1 – 4 , resp.), were isolated along with four previously known glycosides, 5 – 8 , from the MeOH/EtOH extract of the starfish Protoreaster lincki. The structures of 1 – 4 were elucidated by extensive NMR and ESI‐MS techniques as (3β,4β,5α,6β,7α,15α,16β,25S)‐4,6,7,8,15,16,26‐heptahydroxycholestan‐3‐yl 2‐O‐methyl‐β‐d ‐xylopyranoside ( 1 ), (3β,5α,6β,15α,24S)‐3,5,6,8,15‐pentahydroxycholestan‐24‐yl α‐l ‐arabinofuranoside ( 2 ), sodium (3β,6β,15α,16β,24R)‐29‐(β‐d ‐galactofuranosyloxy)‐6,8,16‐trihydroxy‐3‐[(2‐O‐methyl‐β‐d ‐xylopyranosyl)oxy]stigmast‐4‐en‐15‐yl sulfate ( 3 ), and sodium (3β,6β,15α,16β,22E,24R)‐28‐(β‐d ‐galactofuranosyloxy)‐6,8,16‐trihydroxy‐3‐[(2‐O‐methyl‐β‐d ‐xylopyranosyl)oxy]ergosta‐4,22‐dien‐15‐yl sulfate ( 4 ). The unsubstituted β‐d ‐galactofuranose residue at C(28) or C(29) of the side chains was found in starfish steroidal glycosides for the first time. Compounds 1 – 4 significantly decreased the intracellular reactive oxygen species (ROS) content in RAW 264.7 murine macrophages at induction by proinflammatory endotoxic lipopolysaccharide (LPS) from E. coli.     

Synthesis,Chemical Characterization,DNA Binding,Antioxidant, Antibacterial,and Antifungal Activities of Ferrocence Incorporated Selenoureas

Ferrocene‐incorporated selenoureas 1‐(4‐methoxybenzoyl)‐3‐(4‐ferrocenylphenyl)selenourea (P4Me), 1‐(3‐methoxybenzoyl)‐3‐(4‐ferrocenylphenyl)selenourea (P3Me), and 1‐(2‐methoxybenzoyl)‐3‐(4‐ferrocenylphenyl)selenourea (P2Me) were synthesized and characterized by nuclear magnetic resonance, Fourier transform infrared spectroscopy, atomic absorption spectroscopy, CHNS, and single‐crystal X‐ray diffraction. DNA interaction of the compounds was investigated with cyclic voltammetry, UV–visible spectroscopy, and viscometry, which is a prerequisite for anticancer agents. Drug‐DNA binding constant was found to vary in the sequence: K_P4Me (4.9000 × 10⁴ M^?1) > K_P2Me (2.318 × 10⁴ M^?1) > K_P3Me (1.296 × 10⁴ M^?1). Antioxidant (1,1‐diphenyl‐2‐picrylhydrazyl), antifungal (against Faussarium solani and Helmentosporium sativum), and antibacterial (against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Bacillus subtilis) activities have also been reported in addition.     

Caffeoylquinic Acids,Cytotoxic, Antioxidant,Acetylcholinesterase and Tyrosinase Enzyme Inhibitory Activities of Six Inula Species from Bulgaria

Chlorogenic (5‐CQA), 1,5‐, 3,5‐, 4,5‐ and 3,4‐dicaffeoylquinic (DCQA) acids were identified and quantified in the methanol extracts of Inula oculus‐christi L., I. bifrons L., I. aschersoniana Janka var. aschersoniana, I. ensifolia L., I. conyza (Griess .) DC. and I. germanica L. by HPLC analysis. The amount of 5‐CQA varied from 5.48 to 28.44 mg/g DE and the highest content was detected in I. ensifolia. 1,5‐DCQA (4.05–55.25 mg/g DE) was the most abundant dicaffeoyl ester of quinic acid followed by 3,5‐DCQA, 4,5‐DCQA and 3,4‐DCQA. The extract of I. ensifolia showed the highest total phenolic content (119.92±0.95 mg GAE/g DE) and exhibited the strongest DPPH radical scavenging activity (69.41±0.55 %). I. bifrons extract was found to be the most active sample against ABTS^.+ (TEAC 0.257±0.012 mg/mL) and the best tyrosinase inhibitor. The studied extracts demonstrated a low inhibitory effect towards acetylcholinesterase and possessed low cytotoxicity in concentration range from 10 to 300 μg/mL toward non‐cancer (MDCK II) and cancer (A 549) cells.     

The Chemical Diversity of Lantana camara: Analyses of Essential Oil Samples from Cuba,Nepal, and Yemen

The aerial parts of Lantana camara L. were collected from three different geographical locations: Artemisa (Cuba), Biratnagar (Nepal), and Sana'a (Yemen). The essential oils were obtained by hydrodistillation and analyzed by gas chromatography/mass spectrometry. A cluster analysis of 39 L. camara essential oil compositions revealed eight major chemotypes: β‐caryophyllene, germacrene D, ar‐curcumene/zingiberene, γ‐curcumen‐15‐al/epi‐β‐bisabolol, (E)‐nerolidol, davanone, eugenol/alloaromadendrene, and carvone. The sample from Cuba falls into the group dominated by (E)‐nerolidol, the sample from Nepal is a davanone chemotype, and the sample from Yemen belongs to the β‐caryophyllene chemotype. The chemical composition of L. camara oil plays a role in the biological activity; the β‐caryophyllene and (E)‐nerolidol chemotypes showed antimicrobial and cytotoxic activities.     

Synthesis,Molecular Properties Prediction and Antimicrobial Activity of Imidazolyl Schiff Bases,Triazoles and Azetidinones

Benzylidenehydrazinyl imidazoles ( 3 ) are prepared from 2‐hydrazinyl imidazoles ( 2 ) on treatment with hydrazine. The imine functionality in 3 is utilized to develop 5′‐aryl‐N‐(4‐aryl‐1H‐imidazol‐2‐yl)‐1H‐1,2,3‐triazol‐1‐amines ( 5 ) by 1,3‐dipolar cycloaddition of diazomethane followed by aromatization with I₂ in DMSO. Compounds 3 are also explored to prepare 4′‐aryl‐1‐(4‐aryl‐1H‐imidazol‐2‐ylamino)‐3‐chloroazetidin‐2‐ones ( 6 ) on treatment with chloroacetyl chloride. The Molinspiration calculations predicted that 3 , 5 and 6 have molecular hydrophobicity, conformational flexibility, good intestinal absorption and bioactivity scores. The chloro, bromo and nitro substituted imidazolyl azetidinones ( 6c , 6d , 6f ) and nitro substituted imidazolyl triazole ( 5f ) exhibited excellent antibacterial activity on B. subtilis, whereas chloro and nitro substituted imidazolyl triazoles ( 5c , 5f ) showed prominent antifungal activity on A. niger.     

Brucin,an antibacterial peptide derived from fruit protein of Fructus Bruceae,Brucea javanica (L.) Merr

A novel antibacterial peptide specific to Streptococcus pyogenes was produced from dried fruit protein of Brucea javanica (L.) Merr. A mixture of active peptides from the fruit protein was produced in vitro by pepsin hydrolysis. The hydrolysate was purified by reverse‐phase HPLC, and antimicrobial peptides active against Gram‐negative and Gram‐positive bacteria were analysed using SDS‐PAGE and nanoLC‐MS/MS. Here, four possible peptides were obtained and chemically synthesized for comparative study of the growth inhibition of Strep. pyogenes. One chemically synthesized peptide with a molecular mass of 1168·31 Da, His‐Thr‐Leu‐Cys‐Met‐Asp‐Gly‐Gly‐Ala‐Thr‐Tyr, showed the most potent antibacterial activity against Strep. pyogenes. This 11‐amino acid peptide was named Brucin. Its bacterial inhibitory activity was 16‐fold and 12·5‐fold higher than penicillin G and chloramphenicol, respectively, with a MIC value of 20 μmol l^?1. The results suggest that Brucin, a potent antibiotic peptide, may be developed as an alternative drug for the treatment of the disease caused by Strep. pyogenes.

Significance and Impact of the Study

An antibacterial peptide, named Brucin with specificity for Streptococcus pyogenes, was produced in vitro from dried fruit protein of Brucea javanica (L.) Merr. by pepsin‐catalysed hydrolysis. Its inhibitory activity towards the Gram‐positive bacteria was higher than penicillin G and chloramphenicol. The result suggested that Brucin may be applied for the treatment of the disease caused by Strep. pyogenes^*.     

Volatile‐Oils Composition,and Bioactivity of the Essential Oils of Plectranthus barbatus,P. neochilus,and P. ornatus Grown in Portugal

Volatile‐oils chemical composition and bioactivity of the essentail oils from Plectranthus barbatus, P. neochilus, and P. ornatus (Lamiaceae) were assessed. Aerial parts from these three related Plectranthus species were collected from cultivated plants grown in Portugal, during vegetative and flowering phases. Volatiles, isolated by distillation? extraction, were analyzed by GC and GC/MS. Monoterpene hydrocarbons (12–74%) and sesquiterpene hydrocarbons (4–45%) constituted the main fractions in all volatiles. α‐Pinene ( 3 ; 12–67%), oct‐1‐en‐3‐ol ( 6 ; traces–28%), β‐pinene ( 7 ; 0.1–22%), and β‐caryophyllene ( 50 ; 7–12%) dominated P. barbatus volatiles. P. neochilus major volatile components were α‐terpenyl acetate ( 41 ; traces–48%), α‐thujone ( 2 ; 2–28%), β‐caryophyllene ( 50 ; 2–28%), β‐pinene ( 7 ; 1–25%), and α‐pinene ( 3 ; 1–19%). Oct‐1‐en‐3‐ol ( 6 ; 13–31%), β‐pinene ( 7 ; 11–24%), α‐pinene ( 3 ; 11–19%), and β‐caryophyllene ( 50 ; traces–11%) were the main constituents from P. ornatus volatiles. These chemical compositions were rather different from those previously found for specimens harvested in Africa and Brazil. Moreover, the volatiles from the flowers are herewith reported for the first time. Essential oils, isolated by hydrodistillation from leaves and stems, showed a yellowish color and unpleasant odor, with yields ranging from 0.08% to 0.84% (v/dry weight). Antioxidant and antimicrobial activities of the essential oils were evaluated by DPPH^. and TBARS assays, and agar disc‐diffusion method, respectively. Results showed low or moderate antioxidant capacity and significant antimicrobial activity against Gram‐positive bacteria.     

Hypoxia induces BMP‐2 expression via ILK,Akt, mTOR,and HIF‐1 pathways in osteoblasts

It has been shown that hypoxia stimulation regulates bone formation, maintenance, and repair. Bone morphogenetic protein (BMP) plays important roles in osteoblastic differentiation and bone formation. However, the effects of hypoxia exposure on BMP‐2 expression in cultured osteoblasts are largely unknown. Here we found that hypoxia stimulation increased mRNA and protein levels of BMP‐2 by qPCR, Western blot and ELISA assay in osteoblastic cells MG‐63, hFOB and bone marrow stromal cells M2‐10B4. Integrin‐linked kinase (ILK) inhibitor (KP‐392), Akt inhibitor (1L‐6‐hydroxymethyl‐chiro‐inositol‐2‐[(R)‐2‐O‐methyl‐3‐O‐octadecylcarbonate]) or mammalian target of rapamycin (mTOR) inhibitor (rapamycin) inhibited the potentiating action of hypoxia. Exposure to hypoxia increased the kinase activity of ILK and phosphorylation of Akt and mTOR. Furthermore, hypoxia also increased the stability and activity of HIF‐1 protein. The binding of HIF‐1α to the HRE elements after exposure to hypoxia was measured by EMSA assay. Moreover, the use of pharmacological inhibitors or genetic inhibition revealed that both ILK/Akt and mTOR signaling pathway were potentially required for hypoxia‐induced HIF‐1α activation and subsequent BMP‐2 up‐regulation. Taken together, our results provide evidence that hypoxia enhances BMP‐2 expression in osteoblasts by an HIF‐1α‐dependent mechanism involving the activation of ILK/Akt and mTOR pathways. J. Cell. Physiol. 223:810–818, 2010. © 2010 Wiley‐Liss, Inc.     

Nucleolipids of the Cancerostatic 5‐Fluorouridine: Synthesis,Adherence to Oligonucleotides,and Incorporation in Artificial Lipid Bilayers

5‐Fluorouridine ( 1a ) was converted to its N(3)‐farnesylated nucleoterpene derivative 8 by direct alkylation with farnesyl bromide ( 4 ). Reaction of the cancerostatic 1a with either acetone, heptan‐4‐one, nonadecan‐10‐one, or hentriacontan‐16‐one afforded the 2′,3′‐O‐ketals 2a – 2d . Compound 2b was then first farnesylated (→ 5 ) and subsequently phosphitylated to give the phosphoramidite 6 . The ketal 2c was directly 5′‐phosphitylated without farnesylation of the base to give the phosphoramidite 7 . Moreover, the recently prepared cyclic 2′,3′‐O‐ketal 11 was 5′‐phosphitylated to yield the phosphoramidite 12 . The 2′,3′‐O‐isopropylidene derivative 2a proved to be too labile to be converted to a phosphoramidite. All novel derivatives of 1a were unequivocally characterized by NMR and UV spectroscopy and ESI mass spectrometry, as well as by elemental analyses. The lipophilicity of the phosphoramidite precursors were characterized by both their retention times in RP‐18 HPLC and by calculated log P values. The phosphoramidites 6, 7 , and 12 were exemplarily used for the preparation of four terminally lipophilized oligodeoxynucleotides carrying a cyanine‐3 or a cyanine‐5 residue at the 5′‐(n–1) position (i.e., 14 – 17 ). Their incorporation in an artificial lipid bilayer was studied by single‐molecule fluorescence spectroscopy and fluorescence microscopy.     

ENDOGENOUS CYTOKININS,AUXINS, AND ABSCISIC ACID IN RED ALGAE FROM BRAZIL1

Endogenous cytokinins, auxins, and abscisic acid (ABA) were identified and quantified in 11 red algae collected from the Brazilian coast. Field materials and two isolates cultured in the laboratory were extracted with various solvents and buffers containing a mixture of appropriate internal standards, purified by solid‐phase extraction followed by immunoaffinity chromatography, and analyzed by liquid chromatography–tandem mass spectrometry. Isoprenoid cytokinins (free and conjugated forms of isopentenyladenine [iP], cis‐zeatin [cZ], and trans‐zeatin [tZ]) were detected in all species with concentrations of cZ and iP forms being higher than tZ forms. Dihydrozeatin (DHZ) and its metabolites were only detected at very low levels in nine of the studied species. Aromatic cytokinins (6‐benzylaminopurine [BA], ortho‐ and meta‐topolin [oT and mT]) were not detected in any of the samples. The cytokinin profile of Chondracanthus teedei (Mert. ex Roth) Kütz. was distinct in comparison to other species with para‐topolin (pT) derivatives detected in low concentrations. The main auxins present in all species were free indole‐3‐acetic acid (IAA) and indole‐3‐acetamide (IAM). Indole‐3‐ethanol (IEt), indole‐3‐acetyl glutamic acid (IAGlu), and indole‐3‐acetyl leucine (IALeu) were detected in a few species at low concentrations. ABA was present in all species analyzed except for Hypnea nigrescens Grev. ex J. Agardh. No ABA conjugates were detected in any species. These results confirm that cytokinins, auxins, and ABA were common constituents in red seaweeds, with this being the first report of the occurrence of ABA in Rhodophyta. The complexity of the hormone profiles suggests that plant hormones play a role in regulating physiological processes in Rhodophyta.     

The pigment composition of Phaeocystis antarctica (Haptophyceae) under various conditions of light,temperature, salinity,and iron

The pigment composition of Phaeocystis antarctica was monitored under various conditions of light, temperature, salinity, and iron. 19′‐Hexanoyloxyfucoxanthin (Hex‐fuco) always constituted the major light‐harvesting pigment, with remarkably stable ratios of Hex‐fuco‐to‐chl a under the various environmental conditions. Increased pigment‐to‐chl a ratios at low irradiance confirmed the light‐harvesting function of Fucoxanthin (Fuco), 19′‐Hexanoyloxy‐4‐ketofucoxanthin (Hex‐kfuco), 19′‐butanoyloxyfucoxanthin (But‐fuco), and chl c2 and c3. Increased pigment‐to‐chl a ratios at high irradiance, low iron concentrations, and to a lesser extent at high salinity confirmed the photoprotective function of diadinoxanthin, diatoxanthin, and ß,ß‐carotene. Pigment ratios were not always according to expectations. The consistent increase in But‐fuco/chl at high temperature, high salinity, and low iron suggests a role in photoprotection rather than in light harvesting. Low Hex‐kfuco/chl ratios at high salinity were consistent with a role as light harvester, but the high ratios at high temperature were not, leaving the function of Hex‐kfuco enigmatic. Dedicated experiments were performed to test whether or not the light‐harvesting pigment Fuco could be converted into its structural relative Hex‐fuco, and vice versa, in response to exposure to light shifts. Rapid conversions could not be confirmed, but long‐term conversions cannot be excluded. New pigment ratios are proposed for chemotaxonomic applications. The ratios will improve pigment‐based diagnosis of algal species in waters dominated by P. antarctica.     

The auxin influx carrier,OsAUX3, regulates rice root development and responses to aluminium stress

In rice, there are five members of the auxin carrier AUXIN1/LIKE AUX1 family; however, the biological functions of the other four members besides OsAUX1 remain unknown. Here, by using CRISPR/Cas9, we constructed two independent OsAUX3 knock‐down lines, osaux3‐1 and osaux3‐2, in wild‐type rice, Hwayoung (WT/HY) and Dongjin (WT/DJ). osaux3‐1 and osaux3‐2 have shorter primary roots (PRs), decreased lateral root (LR) density, and longer root hairs (RHs) compared with their WT. OsAUX3 expression in PRs, LRs, and RHs further supports that OsAUX3 plays a critical role in the regulation of root development. OsAUX3 locates at the plasma membrane and functions as an auxin influx carrier affecting acropetal auxin transport. OsAUX3 is up‐regulated in the root apex under aluminium (Al) stress, and osaux3‐2 is insensitive to Al treatments. Furthermore, 1‐naphthylacetic acid accented the sensitivity of WT/DJ and osaux3‐2 to respond to Al stress. Auxin concentrations, Al contents, and Al‐induced reactive oxygen species‐mediated damage in osaux3‐2 under Al stress are lower than in WT, indicating that OsAUX3 is involved in Al‐induced inhibition of root growth. This study uncovers a novel pathway alleviating Al‐induced oxidative damage by inhibition of acropetal auxin transport and provides a new option for engineering Al‐tolerant rice species.     

Biologically Active Heterocyclic Hybrids Based on Quinazolinone,Benzofuran and Imidazolium Moieties: Synthesis,Characterization, Cytotoxic and Antibacterial Evaluation

Cytotoxic and antimicrobial agents structurally based on quinazolinone, benzofuran and imidazole pharmacophores, have been designed and synthesized. Spectral (IR, ¹H‐NMR) and elemental analysis data established the structures of these novel 3‐[1‐(1‐benzofuran‐2‐yl)‐2‐(4‐oxoquinazolin‐3(4H)‐yl)ethyl]‐1‐methyl‐1H‐imidazol‐3‐ium chloride hybrid derivatives. All the synthesized compounds were evaluated for in vitro cytotoxicity and antimicrobial activities. Cytotoxic evaluation using MTT assay revealed that compounds 12c , 12g and 12i exhibited significant cytotoxicity with IC₅₀ values 1, 1, and 0.57 μm on this cell line, respectively. Biological activity of the synthesized compounds as antibacterial agent were also evaluated against three Gram‐negative (Escherichia coli, Pseudomonas aeruginosa and Salmonella typhi), three Gram‐positive (Staphylococcus aureus, Bacillus subtilis and Listeria monocitogenes) and one yeast‐like fungi (Candida albicans) strains. All compounds 12a  –  12i showed slightly higher activity against Gram‐positive bacteria than the Gram‐negative one. Among the nine new compounds screened, 3‐[1‐(5‐bromo‐1‐benzofuran‐2‐yl)‐2‐(6‐chloro‐4‐oxoquinazolin‐3(4H)‐yl)ethyl]‐1‐methyl‐1H‐imidazol‐3‐ium chloride ( 12e ) has pronounced higher antimicrobial activity against all tested strains. These results demonstrated potential importance of molecular hybridization in the development of new lead molecules with major cytotoxicity and antimicrobial activity.     

Effects of acute and chronic protein intake on metabolism, appetite, and ghrelin during weight loss

Objective: This study evaluated the effects of acute and chronic consumption of higher dietary protein on energy expenditure, macronutrient use, appetite, and appetite‐regulating hormones during weight loss in women. Research Methods and Procedures: Thirty‐eight women chronically consuming a 750 kcal/d energy‐deficit diet with a protein content of 30% (higher protein‐chronic diet, HP‐CD, n = 21) or 18% (normal protein‐chronic diet, NP‐CD, n = 17) for 9 weeks were tested. On separate days, metabolic, appetite, and hormonal responses were measured over 4 hours when the women consumed a higher protein‐acute meal (HP‐AM) (30% of energy as protein) or a normal protein‐acute meal (NP‐AM) (18% of energy as protein). Results: With chronic diet groups combined, HP‐AM led to lower respiratory exchange ratio (0.829 ± 0.005 vs. 0.843 ± 0.008; p < 0.05), lower carbohydrate oxidation (p < 0.05), and higher fat oxidation (p < 0.05) compared with NP‐AM. HP‐AM also led to reduced self‐reported postprandial hunger (p < 0.001) and desire to eat (p < 0.001) and lower postprandial ghrelin (252 ± 16 vs. 274 ± 18 ng/mL · 240 minutes, p < 0.05) compared with NP‐AM. No differences in postprandial energy expenditure (PPEE) occurred between meals. When combining acute meals, respiratory exchange ratio was lower (p < 0.05) and protein oxidation (p < 0.001) was higher in the HP‐CD vs. NP‐CD. An acute meal‐by‐chronic diet interaction was observed with PPEE such that HP‐AM led to greater PPEE in the HP‐CD vs. NP‐CD (28.7 ± 2.7 vs. 19.9 ± 2.7 kcal/min for 195 minutes; p < 0.05). Conclusions: During weight loss, thermogenesis and protein use appear to be influenced by chronic protein intake, while appetite and ghrelin are more responsive to acute protein intake.     

Water- and nutrient-use efficiency of a deciduous species, Vaccinium myrtillus, and an evergreen species, V. vitis-idaea, in a subalpine dwarf shrub heath in the southern Alps, Italy

Periodic measurements of gas‐exchange rates and determinations of foliar N and P concentrations were used for evaluating instantaneous water‐use efficiency and photosynthetic nutrient‐use efficiency in two co‐existing dwarf shrubs of different growth form (V. myrtillus, deciduous, and V. vitis‐idaea, evergreen) in a subalpine heath in the southern Alps of Italy. Those data were compared with cumulative assessments of water‐use efficiency and photosynthetic nutrient‐use efficiency obtained by measuring leaf carbon isotope discrimination in leaf tissues and by estimating nutrient resorption from senescing leaves. V. myrtillus presented higher dry‐weight based rates of net photosynthesis (A_weight) compared to V. vitis‐idaea. A_weight was positively correlated with foliar‐nutrient status and intercellular‐to‐ambient gradient in CO₂ concentrations. A_weight was, furthermore, negatively correlated with leaf specific mass. Instantaneous photosynthetic nutrient‐use efficiency did not differ between the two species but the percentages of N and P pools resorbed from senescing leaves were somewhat higher in the deciduous species. The evergreen species showed lower P concentrations in senescing leaves which indicated a higher proficiency in resorbing phosphorus compared to the deciduous species. In addition, the evergreen species achieved a higher carbon gain per unit foliar N and P, due to a longer mean residence time of both nutrients. The two species did not differ from each other with respect to both instantaneous and long‐term water‐use efficiency. This was consistent with the climatic pattern, showing no sign of water deficiency through the growing season. Current‐year V. vitis‐idaea leaves had a significantly higher Δ¹³C compared to previous‐year leaves, possibly mirroring a long term acclimation of evergreen leaves, as far as they age, to the habitat conditions in the understory where evergreen species are usually confined within mixed dwarf‐shrub communities.     

Function,expression, specificity,diversity and incompatibility of actinobacteriophage parABS systems

More than 180 individual phages infecting hosts in the phylum Actinobacteria have been sequenced and grouped into Cluster A because of their similar overall nucleotide sequences and genome architectures. These Cluster A phages are either temperate or derivatives of temperate parents, and most have an integration cassette near the centre of the genome containing an integrase gene and attP. However, about 20% of the phages lack an integration cassette, which is replaced by a 1.4 kbp segment with predicted partitioning functions, including plasmid‐like parA and parB genes. Phage RedRock forms stable lysogens in Mycobacterium smegmatis in which the prophage replicates at 2.4 copies/chromosome and the partitioning system confers prophage maintenance. The parAB genes are expressed upon RedRock infection of M. smegmatis, but are downregulated once lysogeny is established by binding of RedRock ParB to parS‐L, one of two centromere‐like sites flanking the parAB genes. The RedRock parS‐L and parS‐R sites are composed of eight directly repeated copies of an 8 bp motif that is recognized by ParB. The actinobacteriophage parABS cassettes span considerable sequence diversity and specificity, providing a suite of tools for use in mycobacterial genetics.