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PubMed1990

Synthesis and stability of 2'-deoxyguanosine 3'-monophosphate adducts of dimethyl sulfate, ethylene oxide and styrene oxide.

Deoxyguanosine 3'-monophosphate (dGMP) was alkylated at the 7-position by dimethyl sulfate, ethylene oxide and styrene oxide in aqueous media and glacial acetic acid, respectively, to yield reasonable quantities of the products, which were purified by HPLC. dGMP adducts are needed as standards for the 32P-postlabelling assay. The stability of the adducts was studied at 37 degrees and neutral pH. The half-lives of disappearance of 7-methyl-dGMP and the beta-isomers of the styrene oxide adducts were about 250 min; 7-hydroxy-ethyl-dGMP and the alpha-isomers of the styrene oxide adducts had respective half-lives of 340 and 440 min. In all cases the main degradation product was the corresponding guanine adduct. The results demonstrate considerable lability of the 7-alkylation products of dGMP which has to be taken into consideration in devising the 32P-postlabelling assay.

Alkylating Agents↗
PubMed1997

Synthesis and Further Reactivity of Functionalized Lactam-Derived Enol Triflates.

Pyrrolidinone- and piperidinone-derived enol triflates 2 were prepared in high yield (60-97%) from the corresponding lactams 1 using KHMDS and N-(5-chloro-2-pyridyl)triflimide. A structure-stability study on the less stable pyrrolidinone-derived triflates revealed that an N-tosyl group is essential, and an alpha-ethoxy substituent enhances thermal stability. Substituents at the 3- and 4-position are tolerated. Substitution of the triflate moiety by a wide variety of functional groups was achieved under mild conditions via metal-mediated reactions. Although cuprate couplings proceeded in only moderate yields, several palladium-catalyzed reactions gave good yields of interesting molecules for further synthetic operations (for example, Stille coupling with vinylstannanes, cross-coupling with arylzincs, and carbonylation processes). Preparation of the first enantiopure lactam-derived enol triflate 15 (from (S)-pyroglutamic acid) is described. Enamide hydrogenation of derivative 17 allowed the synthesis of a proline analogue 18 in excellent yield and diastereoselectivity (86% de).

Journal Article↗
PubMed2003

[Stability and occlusion of six different femoral cement restrictors].

Cement restrictors play an integral part in modern cementing technique in total hip arthroplasty. By sealing the femoral cavity, distal cement leakage is prevented and the intramedullary pressure is increased. Thus both the ability of the cement to interdigitate with bone and secondarily the shear strength of the cement bone interface are enhanced. For this purpose various plug models are available, which differ in design and material. Six different cement restrictors were investigated in a biomechanical model with regard to intramedullary implantation pressure, insertion force and in particular stability and sealing ability. We performed a pressure and stability measurement in artificial saw bones during the insertion and standardised cement application and pressurisation. The REX Cement Stop, which is the only intramedullary expandable cement restrictor, yielded the best results in all of the parameters investigated. The flexible gelatin plugs (Biostop G, IMSET, Plugin Tech) also reached a sufficient canal occlusion and stability, but with slightly higher insertion pressures and forces. However, the more rigid polyethylene restrictors (BUCK, Universal Cement Restrictor) showed a reduced stability and poor sealing ability. The latter devices cannot be recommended for use with modern cementing techniques.

Arthroplasty, Replacement, Hip↗
PubMed2001

In vitro and in vivo characterization of 67Ga(3+) complexes with cis,cis-1,3,5-triamino-cyclohexane-N,N',N"-triacetic acid derivatives.

The aim of this study was to investigate the in vitro and in vivo performance of a 67Ga complex with cis,cis-1,3,5-triaminocyclohexane-N,N',N"-triacetic acid (tachta) as a potential ligand for use as a Ga(III) radiopharmaceutical for PET imaging. The radiolabeling procedure, electrophoretic properties, lipophilicity, acid stability, human serum stability and biodistribution in mice of 67Ga(tachta) were investigated. The 67Ga(tachta) complex forms at 10(-3) M tachta concentration at 40 degrees C in 100% yield; it is neutral, non-lipophilic, 90% stable at pH = 4 and 5 and 100% stable at pH = 6, for at least 8 d. Serum stability experiments demonstrated that at 5 hr 67Ga(tachta) exists in serum as a free complex. At 24 hr, 30% of 67Ga(tachta) is reversibly bound to transferrin-albumin fraction of serum, and that this percentage remains unchanged for a period of 4 d. Biodistribution in mice showed that 67Ga(tachta) rapidly clears via the kidneys from the body with less than 10% of injected activity left in the body at 3 hours and only 6% remaining after 24 hr. The complex also cleared rapidly from all of the major organs, with bone showing some slightly increased (1.15% ID/g) 24 hr accumulation, in comparison with the 3 hr time point. Based upon these data, 67Ga(tachta) may be considered as a candidate for developing new Ga(III) radiopharmaceuticals for PET.

Animals↗
PubMed1967

Purification and properties of Streptococcus lactis beta-galactosidase.

beta-Galactosidase of Streptococcus lactis 7962 was partially purified, and its properties were studied. Enzyme from only this strain of numerous lactic streptococci tested was stable in cell exudates prepared by various means. Cell-free extracts of the 7962 strain were prepared by sonic treatment of washed cells previously grown in presence of lactose to fully induce enzyme synthesis. Protamine sulfate precipitation of the nucleic acids and ammonium sulfate precipitation of protein were used for partial purification of the enzyme. The resulting enzyme, when resuspended in cold (5 C) phosphate buffer, was extremely labile. However, ammonium sulfate in high concentrations (0.85 m) stabilized and stimulated beta-galactosidase activity. Sephadex G-200 gel filtration was used to achieve further purification and to monitor homogeneity of the enzyme. Separation of the beta-galactosidase in buffer at 5 C yielded an enzyme elution pattern showing two peaks of activity. However, addition of the enzyme solution in 0.85 m ammonium sulfate to the column equilibrated with the same salt concentration yielded only one peak of enzyme activity. The data suggested that the native enzyme was dissociating into active subunits which were stabilized in the presence of the ammonium sulfate.

Chromatography, Gel↗
PubMed1999

A single amino acid substitution in the cyclin D binding domain of the infected cell protein no. 0 abrogates the neuroinvasiveness of herpes simplex virus without affecting its ability to replicate.

The infected cell protein no. 0 (ICP0) of herpes simplex virus 1 is a promiscuous transactivator shown to enhance the expression of genes introduced into cells by infection or transfection. The protein interacts with several viral and cellular proteins. Earlier studies have shown that ICP0 binds and stabilizes cyclin D3 but does interfere with the phosphorylation of retinoblastoma protein, its major function. Cyclin D3 plays a key role in the transition from G1 to S phase. To define the role of cyclin D3 in productive infection, the ICP0 binding site for cyclin D3 was mapped and mutagenized by substitution of aspartic acid codon 199 with the alanine codon. We report that the substitution precluded the interaction of this protein with cyclin D3 in the yeast two-hybrid system and the stabilization of cyclin D3 in infected cells. A recombinant virus carrying this mutation could not be differentiated from wild-type parent with respect to replication in dividing cells but yielded 10-fold less progeny from infected resting cells and serum-deprived or contact-inhibited human fibroblasts. In mice, the mutant was only slightly less pathogenic than the wild-type parent by intracerebral route but was significantly less neuroinvasive after peripheral inoculation. Replacement of the mutated amino acid with aspartic acid restored wild-type phenotype. Stabilization of cyclin D3 therefore is linked to higher virus yields in nondividing cells and potentially higher virulence in experimental and natural hosts. One function of ICP0 is to scavenge the cell for proteins that could bolster viral replication.

Amino Acid Substitution↗
PubMedDate not supplied

A biomechanical comparison of screw and wire fixation with and without polymethylmethacrylate re-enforcement for acetabular osteotomy stabilization in dogs.

OBJECTIVE: Compare the biomechanical characteristics of screw and wire fixation with and without polymethylmethacrylate (PMMA) re-enforcement for acetabular osteotomy stabilization in dogs. ANIMALS: Pelves removed from 8 adult mixed breed dogs weighing between 25 and 30 kg. PROCEDURE: The pubic symphysis of each pelvis was split and a central transverse acetabular osteotomy was performed. One hemipelvis from each dog was stabilized with the composite fixation (interfragmentary Kirschner wire, two screws and a figure-of-eight orthopedic wire with PMMA). The contralateral hemipelves was stabilized with an interfragmentary Kirschner wire, two screws, and a figure-of-eight orthopedic wire without PMMA. All hemipelves were tested in bending by using a materials testing machine at a cross head speed of 5 mm/min. An extensometer was placed on the dorsomedial surface of the hemipelves centered over acetabular osteotomy to record distraction of the osteotomy during loading. A load/deformation curve and a load/distraction curve was produced for each hemipelvis. The slope for the initial linear portion of the load/deformation curve and the load/distraction curve, yield load and maximum load sustained were compared between repair groups using a paired t-test with P < .05 considered significant. RESULTS: The slope of the load/deformation curve was significantly greater (P = .001) for hemipelves stabilized with the composite fixation (mean +/- SD: 69 +/- 18 N/mm) compared with hemipelves stabilized without PMMA (mean +/- SD: 39 +/- 8 N/mm). There was no significant difference (P = .593) between repair groups in the slope of the load/distraction curves as measured on the extensometer. Yield load was significantly greater (P = .0002) for hemipelves stabilized with the composite fixation (mean +/- SD: 184 +/- 25 N) compared to hemipelves stabilized without PMMA (mean +/- SD: 74 +/- 12 N). Maximum load sustained was also significantly greater (P = .013) for hemipelves stabilized with the composite fixation (mean +/- SD: 396 +/- 71 N) compared to hemipelves stabilized without PMMA (mean +/- SD: 265 +/- 94 N). Failure of hemipelves stabilized with the composite fixation occurred primarily by ventrolateral bending of the cranial and caudal pelvic segments at the osteotomy site. Failure of hemipelves stabilized without PMMA occurred by ventrolateral bending of the cranial and caudal pelvic segments at the osteotomy site with pronounced concurrent ventrolateral rotation of the cranial pelvic segment. CONCLUSION: PMMA improves the mechanical characteristics of acetabular fracture fixation, at least in part by neutralization of rotational forces. The results of this study justify use of PMMA as a component of the composite fixation when repairing acetabular fractures.

Acetabulum↗
PubMed2002

Water-stabilized cavitands.

Tetrabenzimidazole cavitands 4 were prepared by condensation of ortho esters with octaamino cavitand 3 in 70-80% yield. Molecular modeling predicted that no intramolecular hydrogen bonds are possible between the imidazole fragments in the vase conformation of 4. Instead, this conformation provides four perfect binding sites for hydroxyl-containing molecules through an N-H---O-H---N pattern. Such interactions provide the means for sealing the cavitand's cavity. Accordingly, dry compounds 4 are not soluble in dry CDCl3 but readily dissolve upon addition of small amounts of alcohols or by saturation of the solution with water. 1H NMR spectroscopy revealed that in these solutions molecules 4 adopt a vase conformation while 1D GOESY experiments revealed their monomeric nature. In water-saturated CDCl3, these cavitands 4 form kinetically stable 1:1 inclusion complexes with tetramethylphosphonium bromide and triethylammonium chloride in which the cation is incorporated into the pi-basic cavity. Thus, cavitands 4 are a novel class of open-ended molecular containers capable of the formation of highly kinetically stable complexes upon assistance by hydrogen-bonding water molecules.

Benzimidazoles↗
PubMed2005

Novel fluoropeptidomimetics: synthesis, stability studies and protease inhibition.

Designer fluoropeptidomimetics as protease inhibitors are revealed. The key peptidomimetic region in the inhibitors contains a '-CHF-S-' moiety and is designed to mimic the tetrahedral oxyanion species during the hydrolysis of a peptide bond. Designed fluoropeptidomimetics in aqueous methanol slowly (in several hours to days) yielded the corresponding methyl ether and/or the oxazole derivatives after cyclization. Alkyl substitutions at the C-2 position exhibited enhanced aqueous stability. Nature of '-CHF-S-' moiety and the stabilities of various fluoropeptidomimetics in aqueous solution are disclosed in detail. Fluoropeptidomimetics containing bulky substitutions at P1 such as compounds 15 and 16 exhibited time-dependent loss of activities against chymotrypsin, upto [corrected] 67% and 79% with a Ki of 63 and 120 microM, respectively. Fluoropeptidomimetics are a novel class of protease inhibitors and the next generation of fluoropeptidomimetics should incorporate enhanced stability.

Chymotrypsin↗
PubMed1997

Effects of medium composition and nutrient limitation on loss of the recombinant plasmid pLG669-z and beta-galactosidase expression by Saccharomyces cerevisiae.

The effects of medium composition, nutrient limitation and dilution rate on the loss of the recombinant plasmid pLG669-z and plasmid-borne beta-galactosidase expression were studied in batch and chemostat cultures of Saccharomyces cerevisiae strain CGpLG. The difference in growth rates between plasmid-free and plasmid-containing cells (delta mu) and the rate of segregation (R) were determined and some common factors resulting from the effect of medium composition on plasmid loss were identified. Glucose-limited chemostat cultures of CGpLG grown on defined medium were more stable at higher dilution rates and exhibited delta mu-dominated plasmid loss kinetics. Similar cultures grown on complex medium were more stable at lower dilution rates and exhibited R-dominated plasmid loss kinetics. Overall plasmid stability was greatest in phosphate-limited chemostat cultures grown on defined medium and was least stable in magnesium-limited cultures grown on defined medium. delta mu decreased and R increased with increased dilution rate, irrespective of medium composition. Increased plasmid loss rates at high or low dilution rates would appear to be characteristic of loss kinetics dominated by R or delta mu, respectively. Growth of glucose-limited chemostat cultures on complex medium decreased delta mu values but increased R values, in comparison to those cultures grown on defined medium. Any increased stability that a complex medium-induced reduction of delta mu may have conferred was counteracted by an increased R value. Increased beta-galactosidase productivity was correlated with increased plasmid stability only in glucose-limited chemostat cultures grown on defined medium and not in those grown on complex medium. Previous studies have yielded contrasting responses with regard to the effect of dilution rate on recombinant plasmid loss from S. cerevisiae. Our findings can account for these differences and may be generally valid for the stability of similar yeast plasmid constructs. This information would facilitate the design of bioprocesses, where recombinant plasmid instability results in reduced culture productivity.

Culture Media↗
PubMed1985

Purification of the molybdate-stabilized 9-10 S estradiol receptor from calf uterus.

The molybdate-stabilized calf uterine estradiol receptor has been purified to near-homogeneity by a three-step procedure. Initial purification by heparin-Sepharose chromatography provides a concentrated receptor extract in 40% yield with a 5-10-fold increase in purity. The inclusion of molybdate in phosphate-buffered cytosol enhances 9-10 S receptor stability in high salt and allows elution of the oligomeric receptor complex from heparin-Sepharose with 0.4 M KCl. A second affinity step utilizing estrone carboxymethyloxime coupled to diaminoethyl bis(2-hydroxypropoxy)butane-Sepharose Cl-4B increases purification by a further 1600-fold. High performance liquid chromatography gives homogeneous receptor which migrates on sodium dodecyl sulfate-polyacrylamide gel electrophoresis as a polypeptide of Mr approximately 89,000. The purified molybdate-stabilized receptor sediments at 9.3 +/- 0.2 S (n = 4) in glycerol gradients and has a Stokes radius of 74 +/- 3 A (n = 2) giving a calculated Mr approximately 290,000. These properties and the steroid-binding specificity of the purified receptor bear a close similarity to those found for the 9-10 S receptor in crude cytosol.

Animals↗
PubMed1992

Thermal stabilities of mutant Escherichia coli tryptophan synthase alpha subunits.

Random chemical mutagenesis, in vitro, of the 5' portion of the Escherichia coli trpA gene has yielded 66 mutant alpha subunits containing single amino acid substitutions at 49 different residue sites within the first 121 residues of the protein; this portion of the alpha subunit contains four of the eight alpha helices and three of the eight beta strands in the protein. Sixty-two of the subunits were examined for their heat stabilities by sensitivity to enzymatic inactivation (52 degrees C for 20 min) in crude extracts and by differential scanning calorimetry (DSC) with 29 purified proteins. The enzymatic activities of mutant alpha subunits that contained amino acid substitutions within the alpha and beta secondary structures were more heat labile than the wild-type alpha subunit. Alterations only in three regions, at or immediately C-terminal to the first three beta strands, were stability neutral or stability enhancing with respect to enzymatic inactivation. Enzymatic thermal inactivation appears to be correlated with the relative accessibility of the substituted residues; stability-neutral mutations are found at accessible residual sites, stability-enhancing mutations at buried sites. DSC analyses showed a similar pattern of stabilization/destabilization as indicated by inactivation studies. Tm differences from the wild-type alpha subunit varied +/- 7.6 degrees C. Eighteen mutant proteins containing alterations in helical and sheet structures had Tm's significantly lower (-1.6 to -7.5 degrees C) than the wild-type Tm (59.5 degrees C). In contrast, 6 mutant alpha subunits with alterations in the regions following beta strands 1 and 3 had increased Tm's (+1.4 to +7.6 degrees C). Because of incomplete thermal reversibilities for many of the mutant alpha subunits, most likely due to identifiable aggregated forms in the unfolded state, reliable differences in thermodynamic stability parameters are not possible. The availability of this group of mutant alpha subunits which clearly contain structural alterations should prove useful in defining the roles of certain residues or sequences in the unfolding/folding pathway for this protein when examined by urea/guaninidine denaturation kinetic analysis.

Calorimetry, Differential Scanning↗
PubMed2004

Incidence and characteristics of stroke during 90-day follow-up in patients stabilized after an acute coronary syndrome.

BACKGROUND: Stroke is a rare but serious event that complicates the course of patients with acute coronary syndromes (ACS). The type, outcome, and risk factors of stroke occurring in stabilized patients with ACS have not been previously reported. METHODS: We evaluated stroke incidence, subtypes, and outcomes, in addition to demographics and clinical risk characteristics associated with stroke among patients enrolled in the Sibrafiban versus Aspirin to Yield Maximum Protection from Ischemic Heart Events Post-acute Coronary Syndromes (SYMPHONY) and 2nd SYMPHONY trials. RESULTS: Of 15,904 stabilized patients with ACS, 113 (0.71%) had a stroke over a median follow-up of 90 days. The majority of strokes occurred within 30 days of presentation, and the time course for stroke occurrence paralleled that of myocardial (re)infarction. Most strokes were ischemic (78%), and 52% resulted in moderate or severe disability or death. Patients with stroke were older and more often had hypertension, diabetes, peripheral vascular disease, and atrial fibrillation. Among patients with stroke who had cardiac catheterization, percutaneous coronary intervention, or coronary artery bypass grafting, stroke occurred predominantly after the procedure. No difference in occurrence or type of stroke was observed in the assigned treatment groups. In multivariable modeling age, heart failure, prior stroke, left bundle branch block, and systolic blood pressure predicted the occurrence of stroke. CONCLUSIONS: In patients stabilized after presenting with a spectrum of ACS and treated with sibrafiban and/or aspirin, stroke occurred in fewer than 1% within 90 days but carried a significant mortality and morbidity risk.

Acute Disease↗
PubMed1990

Conditions influencing yield and analysis of 8-hydroxy-2'-deoxyguanosine in oxidatively damaged DNA.

We have conducted studies to obtain practical knowledge regarding the stability, digestion, and analytical determination of the content of 8-hydroxy-2-deoxy-guanosine (8-OHdG) in oxidatively damaged DNA. Utilizing H2O2 plus uv light to form oxidatively damaged DNA, we found that storage of the DNA at -20 degrees C at alkaline pH caused a significant loss of 8-OHdG, whereas storage at -20 degrees C at neutral or acidic pH prevented loss of 8-OHdG. The 8-OHdG within DNA is stable at 100 degrees C for at least 15 min. Formation of 8-OHdG within DNA using uv light and H2O2 as a hydroxyl free radical-generating system yields the highest amounts when low levels of phosphate buffer are used; but the use of Tris or citrate buffers causes a lower yield of 8-OHdG because these buffers act as scavengers for the hydroxyl free radicals. Independent assessment of hydroxyl free radical flux by the use of salicylate trapping allows assessment of competitive radical reactions. Ethanol washing of plastic microfuge tubes prior to DNA enzymatic digestion improved the yield of 8-OHdG and reduced the variability between samples. Digestion of the oxidatively damaged DNA by the use of a method involving DNase I, endonuclease, phosphodiesterase, and alkaline phosphatase produced the highest yield of 8-OHdG.

8-Hydroxy-2'-Deoxyguanosine↗
PubMed1988

Solubilization and hydrodynamic properties of pig atrial muscarinic acetylcholine receptor in dodecyl beta-D-maltoside.

The pig atrial muscarinic acetylcholine receptor (mAcChR) has been solubilized from the membrane-bound state in high yield and in stable conformation by the non-ionic detergent dodecyl beta-D-maltoside (DBM). The yield and selectivity for receptor solubilization is dependent on the detergent/protein ratio during extraction. Extraction at 2 mg of DBM/mg of protein gave a 75% yield of solubilized receptor with a 1.5-fold enrichment. A double-extraction procedure, in which non-receptor protein was first extracted at 0.4 mg of DBM/mg of protein and mAcChR was selectively solubilized by a second extraction at 0.35 mg of DBM/mg of protein, gave a 50% overall yield and a 2.8-fold enrichment. Both preparations had a half-life of about 20 days on ice without addition of muscarinic ligands. Receptor stability was decreased by the presence of cations, particularly bivalent cations, and enhanced by the agonist carbachol. Dissociation constants for the interaction of the DBM-solubilized receptor with the antagonist L-quinuclidinyl benzilate (Kd = 223 pM) and the agonist carbachol (Kd = 100 microM) were similar to those for the digitonin/cholate-solubilized receptor. Pig atrial mAcChR purified in digitonin/cholate and exchanged into DBM displayed reliable hydrodynamic behaviour during sucrose density sedimentation in gradients of 2H2O and H2O and during gel filtration in Sephacryl S-300. DBM is thus the first detergent which will solubilize a stable form of the ligand-free mAcChR in yields similar to those with digitonin, and is the only stabilizing detergent thus far suitable for hydrodynamic studies. DBM is also likely to be similarly useful in studying other membrane proteins for which digitonin has been the solubilizing detergent of choice.

Animals↗
PubMed2002

Energetic and conformational contributions to the stability of Okazaki fragments.

A combination of spectroscopic and calorimetric techniques was used to determine complete thermodynamic profiles accompanying the folding of a model Okazaki fragment with sequence 5'-r(gagga)d(ATCTTTG)-3'/5'-d(CAAAGATTCCTC)-3' and control DNA (with and without thymidine substitutions for uridine), RNA, and hybrid duplexes. Circular dichroism spectroscopy indicated that all DNA duplexes are in the B conformation, the RNA and hybrid duplexes are in the A conformation, and the Okazaki fragment exhibits a spectrum between the A and B conformations. Ultraviolet and differential scanning calorimetry melting experiments reveal that all duplexes unfold in two-state transitions with thermal stabilities that follow the order RNA > OKA > DNA (with thymidines) > hybrids > DNA (with uridines). The dependence of the transition temperature on salt concentration yielded counterion releases in the following order: DNA (with thymidines) > RNA > DNA (with uridines) > OKA > hybrids. Thus, Okazaki fragments have a conformation and charge density between those of its components DNA and hybrid segments. However, the presence of the RNA-DNA/DNA junction confers on them higher stabilities than their component hybrid and DNA segments. The binding of intercalators to an Okazaki hairpin of sequence 5'-r(gc)d(GCU5GCGC)-3' and to its control DNA hairpin has also been studied. The results show that the binding of intercalators to Okazaki fragments is accompanied with higher heats and lower binding affinities, compared with DNA duplexes. This suggests that the presence of an RNA/DNA junction yields a larger surface contact to interact with the phenanthroline ring of the intercalators, which may lead to a larger disruption of the flexible flanking bases of the junction. The overall results suggest that the presence of this junction stabilizes Okazaki fragments and provides a structural feature that can be exploited in the design of drugs to specifically target these molecules.

Calorimetry, Differential Scanning↗
PubMed1997

Improving in vivo folding and stability of a single-chain Fv antibody fragment by loop grafting.

The complementary determining regions (CDRs) from the fluorescein-binding antibody 4-4-20, which yields almost no soluble protein in periplasmic expression in Escherichia coli, were transplanted to the framework of the humanized antibody 4D5. The resulting single-chain Fv fragment (scFv) 4D5Flu showed both a dramatic improvement in soluble expression, even at 37 degrees C, and an improved thermodynamic stability. Antigen affinity was maintained upon this engineering by paying attention to crucial framework-CDR contacts. This demonstrates that the use of superior frameworks is a robust strategy to improve the physical properties of scFv fragments. We also report that the grafted version was selected in phage display over several competing variants of the same antibody with identical binding constant but poorer folding or stability properties. The selection required four panning rounds and a temperature of 37 degrees C and we show that the underlying reason for this selection is a higher fraction of phages carrying functional scFv molecules.

Amino Acid Sequence↗