Abstract:Abstract: The role of marine bacteria playing in the marine ecosystem and the biogeochemical cycles of carbon, and the advances in microbial loop research were reviewed in this paper. The community structure and function and especially the bacterial activity in marine environment and the ecological function of phycosphere bacteria in the frequent occurrence area of Harmful algal blooms (HABs) were discussed as well. The importance and urgency to carry out the study on the coupling effect of “microbial loop - HABs - key microbial groups” were suggested based on the need of frontier research topics.

Abstract:Abstract:[Objective] To characterize the genes of Campylobacter jejuni isolates and to genotype the strains from chicken, cow, duck, pig and red-crowned Crane during 2006 to 2008 by multilocus sequence typing (MLST). [Methods] To choose 7 pairs Campylobacter jejuni home-keeping gene, gltA, aspA, glnA, glyA, pgm, 、tkt and uncA as target gene, PCR was applied to detect 42 samples in East China between 2006-2008. Sequencing, analysis and comparation of the genes were done. [Result] Typing the 42 isolates by MLST and finding 24 new sequence typing types. [Conclusion] MLST is a useful method to evuluate Campylobacter jejuni genes and gene evolution.

Abstract:Abstract:[Objective]An outbreak of disease on the cultured Miichthys miiuy Basilewsky occurred in Zhoushan of Zhejiang province. The symptom displayed as skin ulceration and the inside apparatus turned white. [Methods]We isolated a dominant bacterial strain from the diseased Miichthys and assigned it as strain 090212. The artificial infection test proved that the isolate 090212 was the pathogenic bacterium that caused the disease. We applied physiological and biochemical characterization and API system in the bacterial classification. In order to confirm the result,we amplified a 1458bp sequence of 090212’s 16S rDNA and compared with other Vibrio in GenBank. [Results] The results turned out that 090212 was Gram negative and short rod with single polar flagellum. Homology analysis and phylogenetic study showed that strain 090212 has the highest similarity to Vibrio harveyi, with 99% identity,The sensitivity test of strain 090212 to 28 kinds of antibiotics revealed that the pathogen is sensitive to drugs such as Florfenicol, Tetracycline etc. [Conclusion] This paper revealed for the first time that the causative pathogen, Vibrio harveyi, lead to the mass mortality of Miichthys, which will be helpful in the disease control and health management during Miichthys cultivation.

Abstract:Abstract: [Objective] To screen in vivo genes of Streptococcus pneumoniae controlled by comE gene. [Methods] The comE-deficient strain was constructed by using insertion inactivation and identified by PCR and sequencing. The BALB/c mouse was used as test animal and injected with D39 wild type and D39 comE-deficient strain via intraperitoneal injection. The mice blood was obtained about 24 hours after the injection through posterior orbital venous plexus approach. Then the bacteria induced in vivo were collected from the blood and their RNA were extracted to measure the mRNA expression levels of each in vivo-induced gene by RT-PCR. [Results] The differences of the expressions of 8 in vivo-induced genes in D39 and D39 comE-deficient strain were statistically significant (P<0.05) and in which spd_0300, spd_0414, spd_0622, spd_1663, spd_1719, spd_0235, spd_0873 were up-regulated by transformation and meanwhile spd_1672 was down-regulated. [Conclusion] In vivo-induced genes spd_0300, spd_0414, spd_0622, spd_1663, spd_1719, spd_0235, spd_0873, spd_1672 regulated by transformation were screened out and they may participate in the processes such as growth regulation, temperature reception, carbohydrate metabolism, and lipoids metabolism. The bacterial transformation may enhance the virulence via regulating some in vivo-induced genes expression.

Abstract:Abstract: The protein biosynthesis in cells is an open process cooperatively regulated by many protein factors and enzymes, which form a complicated protein network and signal transduction pathway for mRNA metabolism and protein translation. [Objective] To provide a platform for studying on the function of proteins involving in process of translation termination and the relationship among these proteins in ciliates. [Methods] We constructed the cDNA library of protozoan ciliates Euplotes octocarinatus strictly following the procedure of BD MatchmakerTM Library Construction & Screening kit from Clontech. [Results] We obtained a cDNA library of ciliates Euplotes, the titer of which was -2.437×107cfu/mL, which could suffice for functional gene screen. By using the class II polypeptide release factor (eRF3) as bait protein, we obtained some putative genes, including a partial cDNA putatively encoding RNA helicase. [Conclusion] This library will provide a convenient platform for identifying the functional genes in ciliates.

Abstract:Abstract:[Objective] Genus Thermus represents an ancient descendant within the domain of Bacteria. This research was focused on the isolation and characteristics of Thermus bacteriophages from Tengchong Reihai hot spring. [Methods] Bacteriophage was isolated from Tengchong Rehai hot springs by double-layer plate method, and further characterized by morphology, temperature, pH and organic solvent effection on phage production, DNA restriction endonuclease digestion and protein composition analysis.[Results] One lytic bacteriophage was isolated from Tengchong hot spring. It’s host strain Thermus sp.TC10 belonged to genus Thermus (16S rRNA gene accession number GU119889). This phage has a hexagonal head (67 nm in diameter) and an extremely long tail (837 nm in length and 10 nm in width). The optimum temperature and pH value for production of virons were about 65℃ and pH7.6, respectively. The phage was not sensitive to chloroform. The differences between this phage and the other two Thermus Siphoviridae phages P23-45 and P74-26, which were isolated form Russia's Kamchatka peninsula, demostrated it was a novel bacteriaphage and was denoted as TTSP10 (Tengchong Thermus Siphoviridae phage).

Abstract:Abstract: [Objective] The aim was to study the action mechanism of analogues BF2-A/B of the antimicrobial peptide BuforinⅡ with Escherichia coli (E.coli) genomic DNA. [Methods] The abruption and binding action of peptides to DNA were investigated by agarose electrophoresis and gel retardation assay, respectively. The change of DNA structure after binding with peptides was researched by circular dichroism spectra. The competitive intercalation of peptides and ethidium bromide (EB) into DNA, and the influence of phosphate anion to the interaction between peptides and DNA were analyzed by fluorescence spectra. [Results] BF2-A/B didn’t breakdown the genomic DNA, but they bond to DNA. Both peptides made the two-helical structure of DNA loose, and impaired the accumulation amongst base pairs. BF2-A/B could weaken the fluorescence intensity of EB-DNA complex, which appeared to inhibit the intercalation of EB into DNA. However, the addition of phosphate anion impaired the fluorescent quenching of peptides to DNA-EB complex. [Conclusion] The initial step of peptides binding to DNA was the adhesion of basic amino acid on phosphate group depended on electrostatic attraction. Then the peptides inserted the groove of DNA duplex. The direct intercalation involving phenylalanine and nucleic acid bases participate in the peptides-DNA interaction. The stronger binding affinity of BF2-B than BF2-A attributed to more positive charge and powerful ability of intercalation into groove and base pair of DNA.

Abstract:Abstract: [Objective] To get knowledge about bacterial diversity in Zabuye salt lake With the culture-independent approaches. [Methods] Total DNA was extracted from sediments sample of Zabuye salt lake, Tibet. The 16S rRNA gene was amplified by PCR with Bacterial primer f530/r1492.Then the plasmid library of 16S rRNA genes was constructed. The positive clones were screened on plates with IPTG/X-gal/Ap. Amplified ribosomal DNA restriction analysis ( ARDRA) was carried out with restriction enzymes Hae III, Hha I. With the help of culture-independent approaches, DNA was directly extracted from the sediment samples of Zabuye salt lake. After construction of 16S rRNA gene library, ARDRA (amplified rDNA restriction analysis) analysis was carried out. Some clones were selected to be sequenced according to the ARDRA patterns. These partial sequences of 16S rRNA gene were used for construction of the phylogenetic tree.[Results] The phylogenetic tree showed that some clones (57.14% of total clones) belonged to 23 genera in γ-proteobacteria, ?-proteobacteria, δ-proteobacteria, bacteroidetes, firmicutes, and verrucomicrobia. The rest clones were quite different and were most related with uncultured sequences, forming special division in the tree. [Conclusion] These finding showed much prolific bacteria diversity in Zabuye salt lake.

Abstract:Abstract: [Objective] To isolated a bacterial strain YPP-9, dominantly colonizing the rhizosphere of tomato using root exudate medium. In this study, we investigated the antagnism and disease-controling effect against Ralstonia solanacearum, evaluated the ability to colonize the rhizosphere of tomato, and further analyzed the phylogeny of YPP-9. [Methods] To evaluate the antagnism against R. solanacearum and the biocontrol on tomato bacterial wilt by YPP-9 respectively employing plate culture method and pot experiment in green house. We analyzed the rhizosphere colonization of YPP-9 by PCR-denaturing gradient gel electrophoresis, and also identified the taxonomic position of YPP-9 using morphological and chemotaxonomic characteristics together with 16S rRNA gene phylogenetic analysis. [Results] YPP-9 suppressed the growth of R. solanacearum (strains SSF-4) in vitro with the inhibition zone of 5 mm. The disease-control efficiency against tomato bacterial wilt in pot was 63.4%. YPP-9 also colonized the rhizosphere of tomato well. The colonies were cream in colour after 24 h culture. Cells were gram-positive, rods (1.8-4.1 μm × 0.9-1.1 μm) and formed endospores. Endospores were mainly ellipsoidal to cylindrical and lied in subterminal, and occasionally paracentral, positions in no swollen sporangia. No crystal protein. The pH range for YPP-9 growth was 5.5-8.5 with the optimum at pH 6.0, and the temperature for YPP-9 growth was 20 to 45 degrees with the optimum at 30 degrees. The results of BIOLOG GP2 showed that YPP-9 was Bacillus. Phylogenetic analysis of the 16S rRNA gene sequence revealed that YPP-9 was the most closely related to Bacillus fumarioli, with the sequence similarity of 97.7%. The sequence number was FJ231500. The DNA G+C content was 41.9%. The major menaquinone was MK-7. The dominant fatty acids in cell wall were C14:0 iso, C15:0 iso, C16:0 iso and C16:1ω7c alcohol, with the contents of 28.27%, 19.59%, 12.93% and 10.88%, respectively. [Conclusion] Bacterium YPP-9 strongly inhibited R. Solanacearum in vitro and efficientlyly suppressed the disease development in pot experiment. YPP-9 also colonized the tomato rhizosphere well. Taxonomically, YPP-9 is affiliated to Bacillus, and probably a novel species.

Abstract:Abstracts: [Objective] In order to study the mutual effects of marine obligate hydrocarbonoclastic bacteria in the oil biodegradation process, [Methods] we utilized Alcanivorax sp. 22CO-6, JZ9B and Marinobacter sp. PY97S to construct oil-degrading consortia. Multiple methods including weighting method, GC-FID, GC-MS and TLC-FID were used to analyze and compare the oil degradation rates as well as the chromatographic figures of degraded oil between OHCB pure cultures and defined consortia. [Results] The two OHCB species in the defined consortia 22CO-6+PY97S and JZ9B+PY97S exhibited strong syntrophic effects in the oil biodegradation process. And the degradation rates of oil were increased from 27.81% and 83.52% to 64.03% and 86.89%, respectively. The consortia could degrade aliphatic and aromatic fraction at the same time, including high molecular weight-PAHs chrysene and its alkyl derivatives. [Conclusion] There are obvious syntrophic effets between marine OHCBs Alcanivorax and Marinobacter strains in the oil biodegradation process, which could not only accelerate the oil biodegradation, but also decompose thoroughly the more ecotoxic high molecular weight compounds in crude oil.

Abstract:Abstract：[Objective] We evaluated the cross-protective effect of a 39-kDa adhesive protein (Cp39), recombinant adhesive protein (rCp39), and capsular proteins from in vitro and in vivo grown avian P. multocida in mice. [Methods] The Cp39 was purified by electroelution from capsular proteins of in vivo grown strain C48-3. The rCp39 was expressed in E. coli B21 as a soluble protein by IPTG inducing, and purified with pMALTM protein fusion and purification system. Mice of each group were subcutaneously immunized twice with 100μg of rCp39, Cp39 or capsular proteins from in vivo or in vitro grown strain C48-3 with in complete or incomplete Freund adjuvant at 2-week intervals. Five mice of each group were challenged with 100 LD50 of avian P. multocida strain C48-3 or rabbit P. multocida strain C51-3 two weeks after the second immunization, while the antibody response specific for rCp39 was determined by ELISA. [Results] SDS-PAGE indicated that the Cp39 protein was expressed in vitro and in vivo grown P. multocida. Mice immunized with rCp39, native Cp39 or capsular proteins from in vivo and in vitro grown strain C48-3 were protected completely against the challenge with the homologous strain C48-3, while 60-80% protection was demonstrated in the mice against the challenge with the heterologous strain C51-3. [Conclusion] In conclusion, rCp39 is a cross immunoprotective antigen of P. multocida capsular serogroup A strains, and might be a useful vaccine candidate against fowl cholera.

Abstract:Abstract: [Objective] The purpose of this study was to evaluate the protective effects of surface protective antigen A (SpaA) and its N-teminal protective domain (rSpaA-N) against Erysipelothrix rhusiopathiae infection in mice. [Methods] The SpaA was purified by electroelution from NaOH-extracted antigen of Erysipelothrix rhusiopathiae strain C43311. The rSpaA-N was expressed in E. coli BL21 as a soluble protein by IPTG inducing，and purified with GST affinity chromatography. Mice of each group were subcutaneously immunized three times with 50μg or 100 μg of native SpaA, rSpaA-N or NaOH-extracted antigen with in complete or incomplete Freund adjuvant at 2-week intervals. Five mice of each group were challenged with 100 LD50 of Erysipelothrix rhusiopathiae virulent strain C43065 two weeks after the third immunization, and the specific antibody responses for SpaA was determined by indirect ELISA. [Results] Mice immunized with 50 μg or 100 μg of native SpaA，rSpaA-N，or NaOH-extracted antigen were protected completely against the challenge with strain C43065. There was no significant difference (P<0.05) between the antibody responses observed for native SpaA，rSpaA-N and NaOH-extracted antigen at any dosages. Western blot results indicated that the native SpaA and rSpaA-N were recognized specifically by an antiserum against the native SpaA of strain C43311. [Coclusion] These results demonstrated that the rSpaA-N is a protective antigen of Erysipelothrix rhusiopathiae serotype 2 strains, and might be a useful vaccine candidate against swine erysipelas.

Abstract:Abstract：[Objective] To illuminate the response of mouse macrophage cell line RAW264.7 after infected with Bacille Calmette-Guerin (BCG) in vitro. [Methods] We analyzed the morphology and expression of co-stimulatory molecules on the surface of RAW264.7 after exposed to BCG for 23 hours. Then during the different culture time after discard the BCG in the supernatant, we analyzed the response of RAW264.7 by flow cytometry using carboxyfluorescein diacetate, succinimidyl ester (CFDA-SE), annexin V/PI and Rhodamine 123, respectively. [Results] We observed the phagosome containing BCG under transmission electronic microscope and RAW264.7 cells still grow well after incubated with BCG for 23 hours. We found that the expression level of co-stimulatory molecules, CD40, CD54, CD80, CD86 and CD11b, were elevated evidently, except CD11c, I-Ad and H-2Kd. The fluorescence intensity of BCG stained with CFDA-SE decreased with the prolongation of culture time, but it was still more higher than unstained control four days later. After removal of uninfected BCG, the percents of BCG-infected cell decreased and we didn’t detected BCG-infected cells evidently for 60 h culture. Furthermore, we also found that there was no obvious cell apoptosis for all the time, and the mitochondrial membrane potential of BCG-infected cells increased early and then decreased to the same level as the uninfected control. [Conclusion]These results would be helpful to elucidate the mechanism of BCG vaccination.

Abstract:Abstract: 【Objective】 To evaluate the pathogenicity and immunoprotective effect of a wild strain of Marek's Disease Virus (MDV) after deleting of its meq oncogene. 【Methods】 Total 150 one-day-old SPF chickens were divided into 5 groups of 30 birds each and kept in 5 isolators with positive pressure- filtered air. At first day, 2000 PFU of meq-deleted GX0101Δmeq were inoculated intra-abdominally (i.a.) into each bird in groups 1 and 5, 2000 PFU of commercial vaccine CVI988/Rispens were injected i.a. for group 2. No viral challenge was made in groups 3 and 4 as controls. Five days later, chickens in groups 1, 2, 3 were challenged i.a. with very virulent (vv) MDV strain rMd5. During 90 days after challenge, all dead birds were recorded and checked for necropsy. The tumor-suspected tissues were examined by histo-sections. In the end, all survival birds were killed for necropsy. The samples of heart, liver and spleen were collected for histo-sections.【Results】 Challenge with vv rMd5 caused 87% mortality and 25% of dead birds with gross tumors in non-vaccinated chickens of group 3 but there was no mortality in group 5 inoculated with GX0101Δmeq. Commercial vaccine CVI988/Rispens gave 89% protective index against vv rMd5 challenge and there were 9/42 histo-sections with suspected lymphocyte filtrated nodules in group 2. But vaccination with GX0101Δmeq provided 100% protective index against challenge with vv rMd5 and there was no tumor lesion even in histo-sections in group 1.【Conclusion】 The meq-deleted mutant GX0101Δmeq is able to replicate in cell cultures stably, it has no pathogenicity and oncogenicity to chickens and is able to induce better protective immunity against vvMDV challenge than commercial vaccine CVI988/Rispens.

Abstract:Abstract: [Objective] The aim of the study was explore a new detective target in Vibrio parahaemolyticus which was more specific than others at present, to construct an internal amplification control (IAC), and finally to develop a new PCR system which could effectively eliminate false-negative results. [Methods] Genomic comparison analysis was used to explore V. parahaemolyticus specific targets, which were then evaluated and used to design specific primers. An IAC was constructed by the compound primer technology. PCR parameters were optimized, and its reaction system was developed. [Results] A V. parahaemolyticus species-specific sequence (vp1332) which encodes probable binding protein component of ABC transporter was mined and selected as a detection target. A pair of specific primers (vp1332L/vp1332R) was designed based on this sequence for the development of a PCR assay. An internal amplification control was constructed and added into the PCR detection system, which was co-amplified with the target sequence so as to indicate the existence of inhibitors. Specificity of this PCR system was tested with 296 V. parahaemolyticus strains and 33 non- V. parahaemolyticus strains, and the results showed that there was a 343-bp amplicon resulted from all V. parahaemolyticus strains, while there was no this amplicon but only a 499-bp IAC amplicon appeared for all non- V. parahaemolyticus strains. The detection limit of this assay for purified V. parahaemolyticus genomic DNA was 1.6×102 cfu/mL. Artificial contamination assays showed that V. parahaemolyticus could be detected after eight hours enrichment when the original concentration of this bacterium was 1.24 cfu/25 g. The PCR method developed in this study was also evaluated with Seafood samples, and the results demonstrated that it worked effectively. [Conclusion] A novel PCR method was successfully developed in this study, which could effectively detect V. parahaemolyticus with high accuracy and could especially eliminate false-negative results.

Abstract:Abstract: [Objective] To evaluate the resistance against the adamantine of multi-genotype (H1N1, H3N2 and H9N2) swine influenza viruses isolated from China in recent years by pyrosequencing. [Methods] Mutation in one of five key amino acid residues (positions 26, 27, 30, 31 and 34) within the M2 protein of influenza A viruses, leading to resistance against the adamantine class of anti- influenza drugs. The residues L26, V27, A30, S31,and G34 in the M2 protein were targeted for pyrosequencing, and 10 swine influenza viruses obtained from China during 2004 to 2008 were used to perform the amantadine resistance analysis. [Results] All 5 H1N1 swine influenza viruses were adamantine resistance, three mutations were founded in these isolates, namely V27T,V27I and S31N. Other five isolates, including four H3N2 and one H9N2 swine influenza virus, were proved to be sensitive to amantadine. [Conclusion] Pyrosequencing technology based on the M2 gene can be used to determine the amantadine resistance for multi-genotype swine influenza viruses.

Abstract:Abstract: [Objective] We designed and characterized an oligonucleotide microarray for detecting and subtyping of circulating influenza A virus including subtypes H1N1, H1N2, H3N2, H5N1 and H9N2. [Methods] Based on the sequences of influenza A viruses obtained from the Influenza Virus Resource database of National Center for Biotechnology Information, 46 oligonucleotides probes and one quality control probe were designed to fabricate the microarray. The full-length cDNAs of hemagglutinin and neuraminidase genes were amplified by RT-PCR using universal primers, and the resulting PCR products were labeled and fragmented using Klenow fragment before hybridized with the microarray. A total of 18 different influenza A virus strains representing 5 subtypes and 186 clinical samples were used to validate the specificity and sensitivity of the microarray. [Results] All 18 strains were accurately detected and subtyped by the microarray and no cross hybridization could be detected. The limit of detection for the microarray was approximately 1×104 gene copies of in vitro transcribed RNA. Of the 186 clinical samples, 8 were successfully subtyped as H1N1 and 4 were subtyped as H3N2. [Conclusion] The results show that the microarray is a useful diagnostic method with high specificity and sensitivity, and could be used for influenza surveillance.

Abstract:Abstract:[Objective] To Construct of conjugal transfer system of Streptomyces venezuelae var. Qinlingensis and express of vitreoscilla hemoglobin.[Methods] Intergeneric genetic transfer system was based upon plasmid pSET152 and pHZ1358 from Donor E.coli ET12567(pUZ8002) to Streptomyces venezuelae var. Qinlingensis [Results] Our data showed that Intergeneric genetic transfer system was demonstrated and optimized. Integrating plasmid pJD100 containing Perm Eand construction gene of vhb, constructed by SOE-PCR, was transformed to ET12567(pUZ8002), and then transfered to Streptomyces venezuelae var. Qinlingensis by conjugation. The integrating expression of vhb gene in Streptomyces venezuelae var. Qinlingensis was verified by PCR and CO binding diference spectrum. [Couclusion] In summary, intergeneric genetic transfer system was demonstrated and optimized, and this is the first report to express vhb gene in Streptomyces venezuelae var. Qinlingensis.

Abstract:Abstract：As an opportunistic pathogen, Pseudomonas aeruginosa PAO1 can produce phenazine and its derivatives, which play a critical role in their pathogenesis. In many bacteria, RpoS, the product of rpoS gene, mediates biosynthesis of a set of secondary metabolites. [Objective] This study aims to elucidate rpoS gene’s function and regulation on two phenazine gene clusters in Pseudomonas aeruginosa PAO1. [Methods] The rpoS gene and its upstream and downstream fragments were cloned from the chromosome of Pseudomonas aeruginosa. With the insertion of gentamycin resistance cassette (aacC1), the mutant PA-SG has been created by homologous recombination. Translational fusion plasmids phz1′-′lacZ(pMEZ1) and phz2′-′lacZ(pMEZ2) were constructed, and then were introduced into the wild type strain PAO1 and the mutant PA-SG, respectively. Activities of beta-galactosidase in them were determined with Miller method. [Results] In KMB or PPM medium, beta-galactosidase activity of phz1′-′lacZ in the mutant PA-SG is much more than that in the wild type strain. However, beta-galactosidase activity of phz2′-′lacZ in the wild type strain is 2-3 folds more than that in the mutant PA-SG. [Conclusion] With these results, it is suggested that regulation mediated by rpoS gene on two phenazine loci is specific and different.

Abstract:Abstract: 【Objective】 Glutamyl tRNA Synthetase (Gts) is a protease which catalyzes esterification between tRNA and glutamine. The immunogenicity of Gts was evaluated through immunization and challenge experiment.【methods and results】According to ClustalX analysis, GtS is conservative in Streptococcuci. In this study, we cloned gts from the genome of SC19, and inserted it into prokaryotic expression plasmid pET28a-gts. The recombinant vector was transformed into E. coli BL21. Induced by IPTG, one 58kD protein was expressed and purified by using Ni+–NTA column (Novagen). The purity of rGtS was 93.3% and the concentration of purified protein was 433 μg/mL. We proved the immunogenicity of recombinant protein rGtS by western blot analysis. We immunized Balb/c mice with rGtS and Freund’s adjuvant, and after two boost vaccinations, all mice were challenged with 4 times LD50 amount of SC19 (1.2×109CFU). The survive rate of vaccination group is 50% (4/8), significantly higher than blank vector control group (1/8). 【Conclusion】 These results proved that GtS has certain immunogenicity and can offer partial protection against high dose challenge. Therefore Gts could be a potential candidate of subunit vaccine against Streptococcus suis.

Abstract:Abstract:[Objective] Purify Immunoglobulin (Ig) of Siberian Tiger and prepare monoclonal antibody (mAb) against the Ig, they can be used to develop immunological diagnostic kits for diagnosing infectious disease in Siberian Tiger, and also can be used in basic immunity research. [Methods] The Ig of Siberian tigers was purified with saturated ammonium sulfate combined with recombinant Protein G. The C57BL/6 mice were immunized with the purified Ig. Spleno-cytes of the mice immunized were collected and fused with the mouse myeloma cell line (Sp2/0-Ag14). The positive hybridoma clones were selected by ELISA and were identified by western blot. The sandwich ELISA was used to detect immunocompetence of the purified Ig and the mAb. [Results] We obtained three mouse hybridoma clones in this study can produce mAbs against Ig of Siberian Tiger. The derived McAbs can recognize Ig heavy chain of Siberian Tiger specifically. The biological activity of the Ig and obtained McAbs also can be identified by detecting the antibody induced by panleukopenia virus (FPV-HLJ) vaccine in Siberian Tiger. The antibody also would be useful for assess the vaccine effecacy against the infectious disease on the Siberian Tiger. [Conclusion] Protein G can be used in Ig purification of Siberian Tiger. The obtained McAbs from the hybridoma ADT11 in this study owned strong ability to bind Ig of Siberian Tiger and have a stable immunocompetence. They can be used to develop diagnostic methods for detecting infectious disease in Siberian Tiger and vaccine research.