Top PDF The Effect of Amino-acids and Glycerol Addition on MK-7 Production

The Effect of Amino-acids and Glycerol Addition on MK-7 Production

The Effect of Amino-acids and Glycerol Addition on MK-7 Production

amino acid sources for MK-7 production. As far as rapidly metabolizable carbon sources are available in the fermentation media, expression of genes and enzymes required for transport and metabolism of other carbon energy sources is greatly reduced [7]. Amino acids are essential for production of proteins like heme, which are involved in the respiration process of Bacillus subtilis. Heme is involved in reducing menaquinone to menaquinol in the membrane [7]. When amino acid/s become limiting in the media, specific genes become activated and serve as a positive regulator for some other nitrogen metabolism genes [8]. Based on our pervious study [9] effective carbon and nitrogen sources for higher MK-7 production was investigated and the substrate concentrations (amino acids and glycerol) were also measured during the fermentation process. Yeast extract and soy peptone mixture as the nitrogen source and glycerol as the carbon source were found to be the most effective sources among the factors examined for enhancing MK-7 production. The variation of amino acids concentration was not consistent for all of them. The levels of asparagine, arginine and serine showed 75.67, 11.08 and 7.59 fold decrease, respectively. While the other remaining amino acids showed increase or negligible changes in their concentrations during the fermentation time. Most of the decrease in glycerol and limiting amino acids concentrations in the media was over the first three days of the fermentation where the bulk of the cell growth and MK-7 formation occurred. The objective of this study was to study the effect of addition the limiting nitrogen and carbon sources on MK-7 production.
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MATERIALS AND METHODS Yeast strains

MATERIALS AND METHODS Yeast strains

production rate reached its maximum value at pH 5.92. For the strain Narince 3, both maximum glycerol concentration and glycerol yield remained constant between pH range of 4.00- 5.98, but they considerably increased above pH 5.98. Maximum glycerol concentration was obtained at pH 6.48, while maximum specific glycerol production rate was obtained at pH 6.27. The positive effect of high pH on glycerol production may be explained in relation with the activity of the enzyme aldehyde dehydrogenase. It is reported that, activity of the enzyme aldehyde dehydrogenase is increased at high pH values and acetic acid is produced (18). This oxidation generates a molecule of NADH, which requires reoxidation to maintain the redox balance of the cell. Then, glycerol is formed by the reduction of dihydroxyacetone phosphate to glycerol-3-phosphate, and then to glycerol. It is indicated in the studies concerning industrial glycerol production by S. cerevisiae that, higher glycerol yields were obtained under alkaline conditions. Thus, alkali-steered process is one of the processes which is used commercially for substantial overproduction of glycerol (16,18). Therefore, increase in glycerol production amount with increasing pH is an expected result in our study. When it is thought that S. cerevisiae Kalecik 1 and S. cerevisiae Narince 3 are wine yeast strains, glycerol production amount of those strains at pH values of grape must (3.5-4.2) should be also taken in to account. It is reported that the most available pH range for alcohol fermentation in wine production is 3.8-4.2. This pH range provides the conditions for S. cerevisiae to be dominant species of the fermentation, and also for inhibition of wild yeasts (18). In the present study, it was determined that in the range of pH values of grape must (3.5-4.2), maximum glycerol concentrations obtained in synthetic medium were 8.0 and 7.2 gL -1 for Kalecik 1
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The influence of different stresses on glomalin levels in an arbuscular mycorrhizal fungus--salinity increases glomalin content.

The influence of different stresses on glomalin levels in an arbuscular mycorrhizal fungus--salinity increases glomalin content.

to other cell metabolic pathways. High osmotic stress that is not caused by mineral ions forces organisms to produce low- molecular weight carbohydrates as internal osmoregulators. Glycerol itself is a typical osmoregulator, but AMF likely cannot take up the molecules via their extraradical hyphae since AMF are obligate biotrophs [27]. Osmoregulation under high external molecule concentration such as in our glycerol treatments is therefore costly [28], and the low biomass, low spore abundance and diameter caused by glycerol addition might indicate strong C limitation in the fungus. [29] found a consistent positive relationship between the amount of available carbon to AMF and GRSP levels in different ecosystems, and thus the need to produce osmoregulators might compete with glomalin production for C resources. Our results suggest that glomalin is not involved in amelioration of osmotic stress. Instead, [30] found that the gene for another heat shock protein, a luminal binding protein in
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Effect of the addition of soy lecithin and Yucca schidigera extract on the properties of gelatin and glycerol based biodegradable films

Effect of the addition of soy lecithin and Yucca schidigera extract on the properties of gelatin and glycerol based biodegradable films

similar behavior in films based on potato starch, glycerol and surfactants, where an increasing in the plasticizer concentration resulted in a significant decrease in TS. These authors observed a synergistic effect between glycerol and the surfactants used (Tween 20, Span 80 and soy lecithin) reporting that films containing high concentrations of surfactants, and low amounts of glycerol, showed plastic behavior, with low values of TS and high percentage of elongation. According to these authors, the hydrophilic part of the surfactants could be interacting with glycerol to facilitate its insertion in the polymeric matrix.
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Designed Amino Acid Feed in Improvement of Production and Quality Targets of a Therapeutic Monoclonal Antibody.

Designed Amino Acid Feed in Improvement of Production and Quality Targets of a Therapeutic Monoclonal Antibody.

decreased and Glu concentration remained stable. It seems that these amino acids were neces- sary for the expression phase and the obtained results from the Plackett-Burman analysis con- firmed that. It has been reported that Arg, Cys and Met are important for increasing the mammalian cell culture performance [13, 27]. In addition to the critical role of amino acids in mAbs structure, they play important role in metabolic pathways as mediators [3, 12]. Based on this role, the cell performance and subsequently mAb production are affected by amino acids. Therefore, the positive effect of Asp, Glu and Arg in our experiments seems to be related to their roles in TCA cycle. As an example, Asp, Glu and Arg entered the TCA cycle through oxa- loacetate and α-ketoglutarate, which led to the production of more energy and to efficient cell metabolism [28]. William P.K. Chong et al. demonstrated that Asp from the culture medium contributed to the supply of malate in the cell and that over-expression of malate dehydroge- nase II (MDH II) led to an increase in intracellular ATP and NADH, and improved integral viable cell number and target mAb titer [29].
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Pablo Teixeira Viana3 , João Paulo Santos Roseira2

Pablo Teixeira Viana3 , João Paulo Santos Roseira2

control and the levels 100 and 150 g/kg, but the level 50 g/kg decreased it compared with control. The authors state in their only comment about the NDFD that more studies should be conducted to elucidate the effect. There were no differences between treatments (P>0.05) for milk production (MP) and feed conversion (FC) (Table 7). Several studies in the literature found no significant differences for MP (Chung et al., 2007; Donkin et al., 2009; Wang et al., 2009; Rico et al., 2012; Shin et al., 2012). However, Boyd et al. (2009) evaluated the response of adding glycerol (none, 200 and 400 g) in the diets of lactating cows and found a drop in milk production. On the other hand, Bodarski et al. (2005) evaluated the supply of 300 and 500 mL glycerol/day for lactating cows and found an increase of 14.6 and 12.5% in milk production compared with control. It appears that there are contrasting results between studies with glycerol, thus generating the possibility of interaction between glycerol and the other ingredients of the diet.
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Production, composition and fatty acid profile of milk and butter texture of dairy cows fed ground or pelleted concentrate with sunflower andor lignosulfonate

Production, composition and fatty acid profile of milk and butter texture of dairy cows fed ground or pelleted concentrate with sunflower andor lignosulfonate

ABSTRACT - The objective of this study was to evaluate the milk production, composition, milk fatty acid profile, butter texture and blood parameters of Holstein cows fed corn silage and concentrate containing one of the following: ground sunflower seeds; ground sunflower seeds treated with 50 g of lignosulfonate/kg of sunflower dry matter; pelleted sunflower seeds; or ground sunflower seeds pelleted and treated with 50 g of lignosulfonate/kg of sunflower dry matter. Four lactating cows were used, each with 130±28 days in lactation and a body weight of 569±63 kg. These animals were distributed in a Latin square design with four periods of 21 days each, with 14 days of adaptation and seven days of data collection. The diets were formulated to meet nutritional requirements and had a forage:concentrate ratio of 60:40. The milk fat was lower in the pelleted treatments. The concentrations of 16:1 n-11 and trans18:1 n-9 in the milk increased, and the n-6:n-3 ratio was higher for the pelleted treatments. The firmness and adhesiveness of the butter and the blood parameters analyzed were not affected by the treatments. Addition of lignosulfonate is not effective in protecting polyunsaturated fatty acids from the ruminal bio hydrogenation process, and the pelleting process has little effect on the milk fatty acid profile and can not change the butter texture.
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Effect of the precursor addition on the anticancer alkaloid production using experimental design methodology.

Effect of the precursor addition on the anticancer alkaloid production using experimental design methodology.

Particularmente, o princípio terapêutico deste alcalóide baseia- se principalmente no seu efeito inibidor de enzimas α-manosidase tipo II que participam no processo de glicosilação de proteínas. Estes processos têm sido também associados à presença exagerada de carboidratos na superfície de células cancerígenas e relacio- nados às doenças progressivas e aos processos de metástase, tendo sido seu efeito amplamente estudado por vários grupos de pesquisa. 4-7

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The effect of a high ambient temperature on the apparent ileal digestibility of amino acids and nitrogen in growing pigs

The effect of a high ambient temperature on the apparent ileal digestibility of amino acids and nitrogen in growing pigs

Using a carcass analysis, Ferguson and Gous (2002) reported greater utilization of tryptophan in piglets housed at the high temperatures, when the dietary tryptophan was limited. In the present study there was observed no effect of different ambient temperatures on the apparent ileal digestibility of AA and N. Similarly Koelkebeck et al. (1998) reported that the high ambient temperature had no adverse effects on ileal digestibility of AA, but in laying hens. Contrary to these results Elias and Cline (1991) reported lower digestibility of AA in pigs housed at the ambient temperature which exceeded the upper critical temperature of pigs. However, the digestibility in their study was measured as feacal digestibility. Amino acids in faeces are largely of a microbial origin, their amount and composition does not share undigested dietary AA presented at the end of a small intestine. Therefore, the most accurate method for determination of AA digestibility is the ileal digestibility (Stein et al., 2007).
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The comparison of the structure and microhardness of the tool steel C90 and HS 6-5-2 remelted with the electric arc

The comparison of the structure and microhardness of the tool steel C90 and HS 6-5-2 remelted with the electric arc

The samples were remelted on the surface with the electric arc with the use of the FALTIG 315AC/DC apparatus. The single remelting was applied. The treatment parameters were used: amperage of the electric arc I = 100 A, speed of the electrode movement v=200 mm/min. As the plasma formative gas, the argon was used. The treatment has been conducted at the depart- ment of Foundry and Welding of Rzeszow University of Tech- nology. After the remelting, there has been the conventional tempering done 1x1 hour in a temperature of 200°C for the steel C90 and 2x2 hours in the temperature of 560 °C for the steel HS 6- 5-2. Parameters of tempering (temperature, time and multiplicity) of the tested steels were selected according to the standard PN-EN ISO 4957:2002U. The microhardeness measurements were made with the Hanemanna objective mph 100. The load used was 0,064 N, the operating time of the load was 10 s. Metallographic tests were conducted on the optical microscope - Neophot 2 and Tesla BS-340 electronic scanning microscope.
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Effect of Different Dietary Concentrations of Amino Acids on the Performance of Two Different Broiler Strains

Effect of Different Dietary Concentrations of Amino Acids on the Performance of Two Different Broiler Strains

Treatments consisted of four Nutritional Programs (NP), in which diets were isocaloric with no minimal fixed CP value; however, they contained different concentrations of essential AA. The NP contained Low, Medium, High, or Mixed concentrations of AA. Mixed NP had high AA concentrations until birds were 21 days, followed by regular concentrations (Tables 1 and 2) until the end of the rearing period. The minimum digestible Met+Cys/Lys, Thr/Lys, Arg/Lys, Ile/Lys, and Val/Lys ratios in all NP were 0.74, 0.64, 1.05, 0.65 and 0.75, respectively. These are the ratios typically used by the Brazilian poultry industry. A multiphase feeding regime was applied for all NP, and it was split in five periods: pre-starter (1 to 10 days), starter (11 to 20 days), grower I (21 to 35 days), grower II (36 to 42 days), and finishing (43 to 47 days). Prior to diet formulation, feedstuff AA profile (by high performance liquid chromatography), crude energy and protein were analyzed (AOAC, 2002). The formulated diets were also submitted to the same analyses. Chicken performance was evaluated per period and for the total experimental period relative to body weight (BW), body weight gain (BWG), feed intake (FI) and feed conversion ratio (FCR).
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Affinity chromatography in plasmid DNA purification for therapeutic applications

Affinity chromatography in plasmid DNA purification for therapeutic applications

Arginine has been effectively used in several chromatography methodologies to improve recovery, resolution, and to suppress aggregation. Recently, arginine chro- matography was used to fully separate supercoiled and open circular plasmid DNA isoforms. The specific recognition of supercoiled plasmid isoform by arginine was hypothesised to be due to the ability of arginine matrix to be involved in complex interactions that are partly dependent on the conformation of the DNA molecule. In light of these considerations a study was conducted to understand the several interactions that a DNA molecule can promote with the arginine support, in accord- ance with the chromatographic conditions established. Consequently, knowing the ideal conditions to promote the specific interactions, it could be possible to perform a more targeted and efficient purification. This work describes the chromatography of oligonucleotides with sizes up to 30 bases on the arginine-agarose gel. The effect of several conditions like hydrophobic character of the individual bases, molecular mass of the oligonucleotides, presence of secondary structures, temperature and elution buffer composition (salt and arginine supplemented buffer) was investi- gated. According to previous atomic data referent to possible interactions between amino acids and DNA nucleotides, arginine can preferentially interact with guanine by hydrogen bond, but other interactions (ionic interactions, van der Waals con- tacts, water mediated bonds) may also be present and become dominant depending on the conditions used. The results also revealed that the application of arginine in the elution buffer led to an effective elution of oligonucleotides from the arginine chromatographic support by a competition strategy. In general, it was suggested that the affinity interaction promoted by the arginine support is responsible for the specific recognition of particular oligonucleotide bases, involving multiple interac- tions.
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Promotion of cashmere growth by sulfur supplements in cashmere goats

Promotion of cashmere growth by sulfur supplements in cashmere goats

Na 2 SO 4 is a frequently used sulfate, but ZnSO 4 has better palatability for cashmere goats. Among SAA, methionine is considered to be a limiting amino acid for ruminants (Nimrick et al., 1970; Fenderson & Bergen, 1975; Richardson & Hatfield, 1978). Previous work showed that ruminally protected methionine (RPMet), 2-hydroxy- 4-(methylthio) butyric acid isopropyl ester (HMBi), can provide a substantial quantity of methionine for Holstein dairy cows (Phipps et al., 2008). Peng et al. (2001) found that there were significant differences among the effects of dietary supplementation with different inorganic sulfur sources on nutrient digestion and metabolism in cashmere goats. However, the differences between inorganic and organic sulfur and the effects of the two sulfur sources on related indicators in plasma and cashmere fibres are not yet known. This study was conducted to investigate the impacts of sulfur supplements on cashmere growth in Liaoning cashmere goats and the basic underlying mechanism to elucidate the supplementation effects of ZnSO 4 and HMBi
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Operating characteristics of turbine mixers based on the analysis of power demand of the mixer’s drive

Operating characteristics of turbine mixers based on the analysis of power demand of the mixer’s drive

Mixing processes involve the blending of silica sand, bentonite, coal dust (or mixture) and water. The purpose of mixing is to homogenise the mixture and ensure that the rebonding agent should be uniformly distributed over the grains. This unit was designed for separating casts from the runner system. the number of casts in a batch ranges from 1 to 4 on the given level, there are 1-48 of them on 1-12 levels. The mass of the batch varies from 5 to 12 kg.

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The Role of Amino Acid Permeases and Tryptophan Biosynthesis in Cryptococcus neoformans Survival.

The Role of Amino Acid Permeases and Tryptophan Biosynthesis in Cryptococcus neoformans Survival.

Metabolic diversity is an important factor during microbial adaptation to different environ- ments. Among metabolic processes, amino acid biosynthesis has been demonstrated to be relevant for survival for many microbial pathogens, whereas the association between patho- genesis and amino acid uptake and recycling are less well-established. Cryptococcus neo- formans is an opportunistic fungal pathogen with many habitats. As a result, it faces frequent metabolic shifts and challenges during its life cycle. Here we studied the C. neofor- mans tryptophan biosynthetic pathway and found that the pathway is essential. RNAi indi- cated that interruptions in the biosynthetic pathway render strains inviable. However, auxotroph complementation can be partially achieved by tryptophan uptake when a non preferred nitrogen source and lower growth temperature are applied, suggesting that amino acid permeases may be the target of nitrogen catabolism repression (NCR). We used bioin- formatics to search for amino acid permeases in the C. neoformans and found eight poten- tial global permeases (AAP1 to AAP8). The transcriptional profile of them revealed that they are subjected to regulatory mechanisms which are known to respond to nutritional status in other fungi, such as (i) quality of nitrogen (Nitrogen Catabolism Repression, NCR) and car- bon sources (Carbon Catabolism Repression, CCR), (ii) amino acid availability in the extra- cellular environment (SPS-sensing) and (iii) nutritional deprivation (Global Amino Acid Control, GAAC). This study shows that C. neoformans has fewer amino acid permeases than other model yeasts, and that these proteins may be subjected to complex regulatory mechanisms. Our data suggest that the C. neoformans tryptophan biosynthetic pathway is an excellent pharmacological target. Furthermore, inhibitors of this pathway cause Crypto- coccus growth arrest in vitro.
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Dual dependence of cryobiogical properties of Sf21 cell membrane on the temperature and the concentration of the cryoprotectant.

Dual dependence of cryobiogical properties of Sf21 cell membrane on the temperature and the concentration of the cryoprotectant.

The measured cell osmotic responses and the curve-fitting processes using the 2-p model after the addition of 1.0 M glycerol at four different temperatures are comparatively shown in Figure S2. Figure 3 presents volume change of a Sf21 cell and osmolarity shift of CPA and PBS in the intracellular solution during the solution from the PBS to PBS solution with 1.0 M glycerol at 25uC. The cell membrane permeability coefficients fitted using both the K-K and the 2-p models for the addition of 1.0, 1.5 and 2.0 M glycerol are listed in tables 2, 3, 4, respectively. Apparently, individual variation of the results of the K-K and the 2-p models are quite a few marked-pronounced. In the K-K model, the hydraulic conductivity, the solute permeability coefficient, and the reflection coefficient, are used to characterize the cell membrane. In order to describe the water and solute flux interaction across the cell membrane, the reflection coefficient was introduced [19]. It has Table 2. The cell membrane permeability coefficients of Sf21 for 1.0 M glycerol.
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The Influence of Small Amounts of Aluminium on the Spheroidization of Cast Iron with Cerium Mischmetal

The Influence of Small Amounts of Aluminium on the Spheroidization of Cast Iron with Cerium Mischmetal

The influence of aluminium (added in quantity from about 0.6% to about 2.8%) on both the alloy matrix and the shape of graphite precipitates in cast iron treated with a fixed amounts of cerium mischmetal (0.11%) and ferrosilicon (1.29%) is discussed in the paper. The metallographic examinations were carried out for specimens cut out of the separately cast rods of 20 mm diameter. It was found that the addition of aluminium in the amounts from about 0.6% to about 1.1% to the cast iron containing about 3% of carbon, about 3.7% of silicon (after graphitizing modification), and 0.1% of manganese leads to the occurrence of the ferrite-pearlite matrix containing cementite precipitates in the case of the treatment of the alloy with cerium mischmetal . The increase in the quantity of aluminium up to about 1.9% or up to about 2.8% results either in purely ferrite matrix in this first case or in ferrite matrix containing small amounts of pearlite in the latter one. Nodular graphite precipitates occurred only in cast iron containing 1.9% or 2.8% of aluminium, and the greater aluminium content resulted in the higher degree of graphite spheroidization. The noticeable amount of vermicular graphite precipitates accompanied the nodular graphite.
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An Analysis Of The Difference In Gender Level Of Cassava Production And Access To Land In Abia State Nigeria

An Analysis Of The Difference In Gender Level Of Cassava Production And Access To Land In Abia State Nigeria

From the analysis, it was found that lands were acquired majorly by inheritance and the resultant effect of this is the fragmentation of land during the acquisition and sharing of either family or community lands. The evident of this was seen on the sizes of the land cultivated by both the male and female farmers of which majority of both sexes cultivate a small farm size of 0.1-2.0ha of land with just a few who cultivate a reasonable land size this can also be seen on the number of bag of both garri and fufu produced yearly. However this Land holding in hectares favors more males than females in the study area and females had better production in cassava than male.
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Adaptation to reduced salinity affects the olfactory sensitivity of Senegalese sole (Solea senegalensis Kaup 1858) to Ca2+ and Na+ but not amino acids

Adaptation to reduced salinity affects the olfactory sensitivity of Senegalese sole (Solea senegalensis Kaup 1858) to Ca2+ and Na+ but not amino acids

that gave strong responses to both amino acids and ions; this was usually the anterior–lateral portion of the bulb, close to the olfactory nerve. However, the internal anatomy of the sole meant that access to the whole bulb was restricted; attempts to record good bulbar responses to bile acids, for example, were unsuccessful, even though this fish gives large responses to bile salts when assessed by electro- olfactogram (EOG) recording from the olfactory epithelium (Velez et al., 2007a; Velez et al., 2009). Thus, the poor bulbar responses to bile acids were most probably due to the area of the bulb responding best to bile acids being inaccessible to the recording electrode. The signal was filtered (low-pass 300 Hz, high-pass 3 Hz; Neurolog NL125, Digitimer Ltd) and integrated (time constant 1 s, Neurolog NL703, Digitimer Ltd). Both the direct and integrated signals were digitised (Digidata 1300A, Molecular Devices Corporation, Sunny Vale, CA, USA) and displayed on a computer running Axoscope 9.2 software (Molecular Devices Corporation). All surgical and experimental procedures followed the European Convention for the Protection of Vertebrate Animals Used for Experimental and Other Scientific Purposes (European Treaty Series No. 123) and the Guidelines for the Use of Fishes in Research by the American Fisheries Society (http://www.fisheries.org/afs/ docs/ policy_guidelines2004.pdf).
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Adsorption of amino acids on minerals and the origin of life.

Adsorption of amino acids on minerals and the origin of life.

Os minerais adsorvem muito mais aminoácidos com grupos R carregados que não carregado, portanto, a subseqüente polimeri- zação destes aminoácidos poderia produzir peptídeos/proteínas com uma grande quantidade de aminoácidos com grupos R carregados. Porém, as proteínas dos seres vivos atuais são constituídas de 74% de aminoácidos com grupos R não carregados. Foram discutidos neste artigo diversos mecanismos que poderiam estar envolvidos na produção de peptídeos/proteínas com uma grande proporção de aminoácidos com grupos R não carregados. De todos os experi- mentos aqui discutidos devemos destacar dois e, em ambos, os lipídios estão envolvidos. No primeiro caso, lipídeos (como suge- rido no mundo dos lipídios) em hidrotermais podem ser uma alter- nativa interessante para a síntese de peptídeos, visto que não há necessidade de catalisadores ou minerais para adsorção dos amino- ácidos. No segundo caso, lipossomos selecionaram aminoácidos e peptídeos hidrofóbicos e isto poderia explicar porque 74% dos aminoácidos das proteínas modernas são hidrofóbicos. Portanto, o mecanismo de pré-concentrar os aminoácidos realizado pelos mi- nerais pode não ter sido tão importante quanto se imaginava.
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