Generation and Identification of Monoclonal Antibody Against Porcine Adipocyte Plasma Membrane Proteins

Production of monoclonal antibody against porcine adipocyte plasma membrane proteins to explore a new way of controlling body fat deposition and improving carcass quality is discussed in this article. Membrane proteins of pig adipocyte plasma membrane proteins were extracted with the help of sucrose density gradient centrifugation, and two kinds of proteins were obtained. The monoclonal antibody （designated 3B2 and 3F3） of IgG1 and IgG2b subclass against adipocyte membrane proteins were produced by immunization, with adipocyte membrane proteins as an antigen, and its titer was 1：105 detected by enzyme-linked immunoadsorbent assay （ELISA）. The cell strains were identified by analyzing the number of chromosomes, the heat stability, the acid and alkali, the types and subtypes of immnoglobulin, and its peculiarities and affinities. Through identification, the chromosome number of hybridoma cell strains was from 80 to 100 and the strains formed good hybridomas colonies. The strains＇ affinity constants were 4.63 × 10^9 and 3.75 × 10^9 （mol L^-1）-1, respectively. At the same time, the McAb secreted was stable to environmental factors, such as, temperature, acid, alkali and so on. The monoclonal antibodies had been obtained and their specificity to porcine adipocyte plasma membrane proteins had been identified.

Optimization of Enzymolysis Process of Porcine Serum Protein for Fe-chelating Peptides by Response Surface Methodology

This study was conducted to optimize the hydrolysis of porcine serum protein by response surface methodology （RSM）. Based on single-factor tests, 3- factor 3-level response surface tests were designed by Box-Behnken design method, and the effects of pH, temperature and hydrolysis duration on the response values were analyzed by RSM method. The optimal enzymolysis conditions were obtained as follows： pH value of 7.7, temperature at 46.3 ℃ and time of 7.4 h, under which the predicted degree of hydrolysis was 35.52%, and the chelating rate was 79.41%. This process could provide new ideas for the development of porcine serum protein.

Identification of the strain-specifically truncated nonstructural protein 10 of porcine reproductive and respiratory syndrome virus in infected cells

The nonstructural protein 10（nsp10） of porcine reproductive and respiratory syndrome virus（PRRSV） encodes for helicase which plays a vital role in viral replication. In the present study, a truncated form of nsp10, termed nsp10 a, was found in PRRSV-infected cells and the production of nsp10 a was strain-specific. Mass spectrometric analysis and deletion mutagenesis indicated that nsp10 a may be short of about 70 amino acids in the N terminus of nsp10. Further studies by rescuing recombinant viruses showed that the Glu-69 in nsp10 was the key amino acid for nsp10 a production. Finally, we demonstrated that nsp10 a exerted little influence on the growth kinetics of PRRSV in vitro.

Characteristics,formation mechanism and stability of high internal phase emulsions stabilized by porcine plasma protein (PPP) / carrageenan (CG) hybrid particles

High internal phase emulsions (HIPEs) stabilized by nanoparticles based on biomacromolecules are challenging issues in recent decade.Herein,a newly developed HIPE was investigated by using heat-denatured porcine plasma protein (PPP) nanoparticles at pH 6.5 as emulsifier,and its emulsifying stability could be significantly enhanced by compounding carrageenan (CG).In the miscible system,PPP and CG formed hybrid particles through non-covalent interaction,and the sizes and zeta-potentials of the particles increased significantly along with addition of CG (from 0 to 0.7%,w/v),reached up to about 3.6 μm and −53 mV at 0.5% (w/v),respectively.CG weakened the ability of PPP to lower interfacial tension of oil/water (O/W),but increased the apparent viscosity of the system.The results from CLSM,rheology and stability experiments indicated a significant increasing trend of the HIPEs stability and solid-like characteristics along with addition of CG.Compared with the controls including bovine serum albumin (BSA),BSA-CG and CG alone,PPP-CG hybrid particles had good performance in fabricating and stabilizing the HIPEs.The work revealed the novel function of PPP as emulsifier of HIPEs and so offered the theoretical direction for application of PPP as a mass by-product,as well as an excellent HIPEs system for food,medicine and cosmetics fields.

Protective,controlled-release and embedding mechanism of porcine plasma protein cold-set gel on quercetin:An effective carrier of hydrophobic compounds

Protection and embedding of hydrophobic bioactive compounds using protein hydrogels are emerging focus during the latest decade.In present study,we fabricated the porcine plasma protein(PPP)cold-set gel by microbial transglutaminase(MTGase)and glucono-δ-lactone(GDL)as coupling precursors.As a result,the embedding,protection and controlled-release effect of the gel on vulnerable hydrophobic bioactive components(quercetin(Que)as representative)with proposed molecular mechanisms were investigated in detail.The results showed that high concentration of Que(5 mmol/L)could be loaded with PPP cold-set gel and embedding efficiency(EE)was over 98%.Compared with free Que,the embedded one exhibited significantly higher thermostability,photochemical stability and storage stability(P<0.05).In addition,the gel loaded with 5 mmol L^(−1) of Que had higher swelling potency under gastric(low pH)media and controlled release performance following simulated intestinal digestive pathway.Water holding capacity(WHC)implied that free water molecules played less role in the retention ability of Que in fabricated gel network.Spectral-assisted structural characterization proved that Que was efficiently embedded mainly by generating PPP-Que complex through hydrogen bond and van der Waals force,and the binding site was mainly near Trp residue.This work gave novel insight into the potential use of PPP cold-set gel as an excellent carrier towards protection and selective delivery of vulnerable small hydrophobic nutraceutical compounds.

Amplification of the Full-Length PAMP Gene and Difference of the mRNA Expression Among Three Lean Pig Breeds

To understand the function of porcine adipocyte-special membrane protein （PAMP） gene and the difference of fat deposition ability among various lean pig breeds, a full-length porcine adipocyte-special membrane protein （PAMP） gene was successfully amplified using reverse transcription polymerase chain reaction （RT-PCR） and 5＇-rapid amplification of cDNA end （5＇-RACE）. The open reading frame was 1 587 bp encoding 529 amino acids. The nucleotide sequence of the fulllength PAMP gene was deposited in the GenBank under the accession number EF433431. The PAMP gene mRNA expression was analyzed on three lean pig breeds by quantitative reverse transcription polymerase chain reaction （QRTPCR）. The PAMP gene mRNA levels in YHM （Yorkshire × Hampshire × Meishan） pig and DLY （Duroc × Landrance × Yorkshire） pig were about 0.82 and 0.38 times of that in SW （Shanxi-White） pig, respectively.