Proteins equivalents

Figure 3. Mechanism of microsomal EH-catalyzed hydration of the K-region epoxide enantiomers of BA, BaP, and DMBA. The percentages of the trans-addition product by water for each enantiomeric epoxide are indicated. The enantiomeric composition of the dihydrodiol enantiomers formed from the hydration of DMBA 5S,6R-epoxide was determined using 1 mg protein equivalent of liver microsomes from pheno-barbital-treated rats per ml of incubation mixture and this hydration reaction is highly dependent on the concentration of the microsomal EH (49). The epoxide enantiomer formed predominantly from the respective parent hydrocarbon by liver microsomes from 3-methylcho-lanthrene-treated rats is shown in the box.

Between 0.5 and 80 pg of protein (equivalent to 20-1600 pg/ml) maybe estimated in a microtest plate (96-well plate, flat bottom). 

Two other protein complexes also function in eukaryotic DNA replication. RPA (replication protein A) is a eukaryotic single-stranded DNA-binding protein, equivalent in function to the E. coli SSB protein. RFC (replication/actor (J) is a clamp loader for PCNA and facilitates the assembly of active replication complexes. The subunits of the RFC complex have significant sequence similarity to the subunits of the bacterial clamploading (y) complex. 

The Protein Equivalence Ratio (PER), a criterion for protein nutritional value, is higher for the gel produced protein. 

Figure 4. Decrease in specific viscosity during the hydrolysis of CMC solution by E-3-1, E-3-2, E-3-3, E-3-4, and E-3-5. Reaction mixture consists of 3.0 mL 1% CMC, 7.0 mL 0.1M sodium acetate buffer, pH 4.0, and 2.0 mL enzyme solution containing an amount of protein equivalent to an optical density of 0.05 at 280 nm. The reaction mixture was carried out at 30°C in an Ostwald viscometer.

An answer to this apparent riddle is provided by RNA. Ribonucleic acid is actually a DNA equivalent, since it can store and replicate genetic information. Importantly, it is also a protein equivalent, since it can catalyze critical chemical reactions. Indeed, the first life-forms were probably entirely RNA based, and RNA has remained part of our cellular systems (Watson, 2004). Thus, RNA translates the genetic information coded for in our DNA into information that proteins can understand and act upon and does so in a remarkable manner. 

Samples should contain about 50 to 100 pg protein, equivalent to at least 2 nmol of the least abundant amino acid. 

In set style yoghurt, the cross-linking of the caseins can be exploited to increase the firmness or, in stirred yoghurt, to raise the viscosity level (Figure 19.25). Also shown is the increase in the degree of polymerisation ADP as compared to untreated milk. It is notable that the viscosity level is considerably enhanced by the Tg cross-linking reaction. While for untreated milk a viscosity level of 0.07 Pas can be obtained at a protein concentration of 4.9%, the same viscosity was measured for the Tg treated milk at 3.6%, that is, a very costly increase in protein level can be avoided and a considerable raw material reduction of 1.3% protein, equivalent to about 3.6% milk dry matter, can possibly be achieved. 

The vanadium nitrogenase has been isolated from A. vinelandii and A. chroococcum (Table 1). With the molybdenum in the protein replaced by vanadium, the vanadium nitrogenase resembles its molybdenum counterpart. It has the molybdenum-iron (MoFe) protein equivalent in the vanadium-iron (VFe) protein, as well as the iron (Fe) protein equivalent. 

Some archaeal r-protein operons contain open reading frames (ORFs) that are not present in the equivalent bacterial operon. In many cases, these ORFs code for proteins which show sequence similarity to eucaryal r-proteins. For example, ORF c, d and e in the spc operon of Methanococcus vannielii [100] and Sulfolobus acidocaldarius [Kusser et al., unpublished] code for r-proteins equivalent to the eucaryal r-proteins S4 Rattus norwegicus), L32 Homo sapiens) and LI9 R. norwegicus) respectively. 

Each vial contains 5 mg of drug conjugate (protein equivalent) in a 20-mL amber vial. The inactive ingredients are dextran 40, sucrose, sodium chloride, monobasic and dibasic sodium phosphate. Light-sensitive. 

Predialysis serum albumin Percentage of usual postdialysis or postdrain body weight Subjective global assessment Protein equivalent of total nitrogen appearance (PNA) ... 

As noted already, the hydration level above which the protein heat capacity is constant defines completion of the hydration process. The value estimated for lysozyme is 0.38 g of water/g of protein, equivalent to 300 molecules of water/molecule of lysozyme. With regard to other thermodynamic measurements, the sorption Isotherm is not able to define completion of the hydration process, and there can be difficulty in Interpreting scanning calorimetric experiments in terms of completion of hydration, because different states of the system are being compared (frozen and solution, or native and denatured) and during a scanning calorimetric measurement the system is not at equilibrium, allowing reaction rates to influence the response. 

Figure 7.40 Sense-complementary peptide concepts (a) DNA double helix is maintained throughout by Watson-Crick base pairs, (b) Protein-protein interactions may be driven in part by a peptide/protein equivalent of Watson-Crick base pairs, (c) Specific sense-complementary peptide interactions may provide the basis for understanding. A sense peptide is coded for by the nucleotide sequence in sense mRNA that has the same sequence information as the sense strand of DNA. A corresponding complementary peptide is coded from by the nucleotide sequence in complementary mRNA that has the same sequence information as the complementary strand of DNA. Sense and corresponding complementary peptides are capable of specific interactions suggesting that there may be a peptide/protein binding interaction code associated with the genetic code and its complement.

Figure 9 Yeast5. cerevisiae cell with small daughter cell bud and proteins of arsenate reduction and transport. Acr2p the yeast cytoplasmic arsenate reductase. Acr3p the potential-driven membrane arsenite efflux protein, equivalent to bacterial ArsB. Ycflp the novel As(III)-3 GSH adduct carrier than transports the adduct complex into the cell vacuole compartment, functioning as an ATPase.

Inteins are intervening sequences that are posttranslationally excised from protein precursors. They are the protein equivalent of introns, which are intervening sequences that splice from precursor RNAs. The sequences flanking both sides of... 

Paddon-Jones et al. reported optimal protein synthesis when dietary protein was provided three times per day compared with the same total amount of protein given in various amounts [26, 29]. In patients with PKU, providing amino acid-based medical food throughout the day compared to a single dose of similar protein equivalents had a positive effect on protein synthesis [30]. A positive effect on plasma phenylalanine concentrations was also reported [30]. For patients with a metabolic disorder, providing medical food along with limited whole protein foods is most beneficial to optimize synthesis. 

The LNAA diet differs from the standard low-phenylalanine diet. Whereas the low-phenylalanine diet depends on approximately 80 % of daily protein requirements being supplied from medical foods, the LNAA diet consists of approximately 70-80 % protein from whole protein foods with 20-30 % of protein requirements from LNAA. Calculations should be based on a daily protein intake of 0.8 g protein/kg/day. When prescribing the diet, first, calculate the total daily protein requirement, and then subtract the 70-80 % of total protein from food sources. The remaining 20-30 % of protein equivalents should be supplied as LNAA (Box 11.3). 

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