A floristic investigation of the islet groups Arki and Lipsi (East Aegean Area, Greece)

Arki and Lipsi are two islet groups situated in the NNW part of the prefecture of Dodecannisos (E Aegean area, Greece), which consist of 37 islets in total, of which three (Lipsos, Arki and Marathi) are permanently inhabited. From the area studied 557 taxa of Tracheophytes have been registered and the chorological and life-form analyses of the flora have shown the predominance of the Mediterranean elements and the therophytes, respectively, confirming the Mediterranean character of the flora. However, significant fluctuations have been observed regarding the representation of both, chorological and life-form types, from islet to islet. A comparison of the individual flora of the 37 islets studied, revealed very low floristic similarity even between neighbouring islets (β-diversity). Not one of the taxa registered was present on all 37 islets; yet, 199 taxa were present on only one islet. Eight of the taxa registered in the studied area fall under a protection status according to international lists. The floristic data were statistically evaluated with respect to species-area relationship and other geographical factors such as altitude, minimum distance from a larger inhabited island and sea depth.     

Proteome-wide identification of NEDD8 modification sites reveals distinct proteomes for canonical and atypical NEDDylation

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Enhanced ethanol production,volatile compound biosynthesis and fungicide removal during growth of a newly isolated Saccharomyces cerevisiae strain on enriched pasteurized grape musts

The kinetic behavior of a newly isolated Saccharomyces cerevisiae strain, grown on pasteurized grape musts enriched with industrial sugars, was studied after the addition of various concentrations [0.0 (reference), 0.4 and 2.4 mg/L] of the fungicide quinoxyfen to the medium. Batch‐flask cultures were carried out. Significant quantities of biomass (10.0±0.8 g/L) were produced regardless of quinoxyfen addition to the medium; therefore, the addition of the fungicide did not seriously inhibit biomass production. Ethanol was synthesized in very high quantities in all trials (highest concentrations 106.4–119.2 g/L). A slight decrease of ethanol production in terms of both absolute value and conversion yield of ethanol produced per sugar consumed was, however, observed when the quinoxyfen concentration was increased. The addition of quinoxyfen led to significantly lower ethylic ester levels, which also pertains to the acetates analyzed in this study. Fusel alcohol synthesis seemed to be activated when 0.4 mg/L quinoxyfen was added, but at 2.4 mg/L of added fungicide, no statistically significant differences were observed compared with the control trial. Volatile acid levels did not present a uniform trend in relation with the added fungicide. Finally, the fermentation was accompanied by a significant reduction of the fungicide concentration (79–82 wt% fungicide removal).     

Biotechnological production of the European corn borer sex pheromone in the yeast Yarrowia lipolytica

The European corn borer (ECB) Ostrinia nubilalis is a widespread pest of cereals, particularly maize. Mating disruption with the sex pheromone is a potentially attractive method for managing this pest; however, chemical synthesis of pheromones requires expensive starting materials and catalysts and generates hazardous waste. The goal of this study was to develop a biotechnological method for the production of ECB sex pheromone. Our approach was to engineer the oleaginous yeast Yarrowia lipolytica to produce (Z)-11-tetradecenol (Z11-14:OH), which can then be chemically acetylated to (Z)-11-tetradecenyl acetate (Z11-14:OAc), the main pheromone component of the Z-race of O. nubilalis. First, a C14 platform strain with increased biosynthesis of myristoyl-CoA was obtained by introducing a point mutation into the α-subunit of fatty acid synthase, replacing isoleucine 1220 with phenylalanine (Fas2p^I1220F). The intracellular accumulation of myristic acid increased 8.4-fold. Next, fatty acyl-CoA desaturases (FAD) and fatty acyl-CoA reductases (FAR) from nine different species of Lepidoptera were screened in the C14 platform strain, individually and in combinations. A titer of 29.2 ± 1.6 mg L^-1 Z11-14:OH was reached in small-scale cultivation with an optimal combination of a FAD (Lbo_PPTQ) from Lobesia botrana and FAR (HarFAR) from Helicoverpa armigera. When the second copies of FAD and FAR genes were introduced, the titer improved 2.1-fold. The native FAS1 gene's overexpression led to a further 1.5-fold titer increase, reaching 93.9 ± 11.7 mg L^-1 in small-scale cultivation. When the same engineered strain was cultivated in controlled 1 L bioreactors in fed-batch mode, 188.1 ± 13.4 mg L^-1 of Z11-14:OH was obtained. Fatty alcohols were extracted from the biomass and chemically acetylated to obtain Z11-14:OAc. Electroantennogram experiments showed that males of the Z-race of O. nubilalis were responsive to biologically-derived pheromone blend. Behavioral bioassays in a wind tunnel revealed attraction of male O. nubilalis, although full precopulatory behavior was observed less often than for the chemically synthesized pheromone blend. The study paves the way for the production of ECB pheromone by fermentation.     

Purification and properties of the antizymes of Escherichia coli to ornithine decarboxylase

The purification of the antizymes to ornithine decarboxylase of Escherichia coli to homogeneity is detailed. An acidic component, pI 3.8, and two basic histone-like proteins, pI above 9.5, are described. The two latter proteins constitute approximately 90% of the total antizyme activity.     

Change in kyphosis does not affect the risk of falling in postmenopausal osteopenic and osteoporotic women

Objectives:To examine the influence of the annual change in kyphosis on the risk of falling in postmenopausal osteopenic and osteoporotic women.Methods:This prospective observational study included 498 postmenopausal Greek women over the age of 50, suffering from either osteoporosis or osteopenia. Data on age, height, weight, and self-reported falls were collected. Additionally, we evaluated the degree of the kyphosis angle, the balance, the mobility, the functionality and the handgrip strength on both hands of each subject using the Debrunner kyphometer, the Berg Balance Scale, the Timed-Up-and-Go test, the 30 Seconds Sit-to-Stand test and the Jamar Hydraulic Hand Dynamometer, respectively. All the above data were recorded at the baseline visit and the 12-month follow-up visit for each participant.Results:All examined variables presented a statistically significant change at the 12-month follow-up visit. Nevertheless, the annual change in kyphosis did not show any association with the risk of falling.Conclusion:No association was shown between the annual change in kyphosis and the risk of falling in postmenopausal osteopenic and osteoporotic women, nor bears any substantial prognostic value for future falls.     

Incubation temperature and energy expenditure during development in loggerhead sea turtle embryos

The choice of a suitable nest habitat by oviparous reptiles that deposit eggs into a nest and provide no subsequent parental care is likely to play a major role in the survival of the offspring. In particular variations in nest temperature may influence the rate at which embryos utilise their yolk energy.The effects of nest temperature on total energy use are however complex. High temperatures may advance development and shorten the time to hatching, thereby reducing energy use, but they also stimulate metabolic rate increasing energy use. The net effect of temperature on total energy demands is therefore uncertain.Oxygen consumption (VO₂) and carbon dioxide production (VCO₂) were measured by open-flow respirometry during the incubation of loggerhead sea turtle eggs at three temperatures (27.6, 30.0 and 31.8 °C).At each temperature, VO₂ and VCO₂ showed a peak followed by a decline to hatching. Incubation temperature was negatively related to incubation duration and positively related to the maximum metabolic rate of the embryos. Peak VO₂ was 74.8 ml/egg/day at 27.6 °C, 91.9 ml/egg/day at 30.0 °C, and 97.9 ml/egg/day at 31.8 °C. Peak VO₂ occurred closer to hatching in eggs incubated at higher temperatures.Total energy expenditure was greatest at the lowest incubation temperature and lowest at the highest temperature. Total VO₂ and VCO₂ were 1777 ml/egg and 1226 ml/egg, respectively, at 27.6 °C, 1680 ml/egg and 1235 ml/egg at 30.0 °C, and 1613 ml/egg and 1191 ml/egg at 31.8 °C. Using the actual RQ values, this corresponds to a cost of development of 34,963 J/egg at 27.6 °C, 33,403 J/egg at 30.0 °C, and 32,107 J/egg at 31.8 °C.At all temperatures, the calculated respiratory quotient values did not suggest that yolk substrates were oxidised proportionately, but more likely indicated their sequential use.Nest temperatures may play a key role in energy use, with cooler temperature nests increasing the overall energy demands placed on developing embryos.     

Mentha spicata and Salvia fruticosa composts as soil amendments in tomato cultivation

Τhe potential use of the aromatic plants Mentha spicata L. (spearmint) and Salvia fruticosa Mill. (sage) as soil amendments was evaluated. For this purpose, tomato seeds were sown in pots that had been filled with composts made from these plants and mixed with soil collected from an organically cultivated tomato field. A 2?×?2?×?4 [two types of fertilizer (synthetic and organic), two types of compost (M. spicata and S. fruticosa) and four compost rates (0%, 2%, 4% and 8%, w/w)] factorial experiment was used; the experiment was conducted twice in a growth chamber and lasted 60 days. At 0, 20, 40 and 60 days, after the establishment of the experiment, the soil bacterial and fungal abundance, the growth of nitrifying bacteria, the number of emerging weeds and the shoot length of tomato plants were measured in all treatments; at the end of the experiment, the above and belowground biomass of tomato plants was also determined. Soil microbial density increased with increasing compost rate of both species; the highest fungal and bacterial densities were recorded at 40 and 60 days, after the establishment of the experiment, respectively. Nitrifying bacteria were present in all treatments and at all sampling times. Both composts had a stimulating effect on tomato growth, which was remarkably pronounced with M. spicata. In contrast, weed emergence was reduced, but only in soils amended with M. spicata. The results suggest that M. spicata compost added at a rate of 4% to 8% is a very promising soil amendment, since it stimulates tomato growth, increases soil bacterial and fungal abundance and inhibits weed emergence. Further research is needed to elucidate the mode of action of M. spicata compost, its effect under field conditions and its possible use in mixed crop, rotational crop or cover crop systems.