Efficacy and safety profile of drug-eluting beads transarterial chemoembolization by CalliSpheres® beads in Chinese hepatocellular carcinoma patients.

BACKGROUND: This study aimed to investigate the efficacy and safety of drug eluting beads transarterial chemoembolization (DEB-TACE) treatment by CalliSpheres® in Chinese patients with hepatocellular carcinoma (HCC) as well as the predicting factors for response. METHODS: 99 patients with HCC were consecutively enrolled in this study. All participants were treated by CalliSpheres® DEB-TACE. Clinical response was evaluated according to modified Response Evaluation Criteria in Solid Tumors (mRECIST) criteria. Common Terminology Criteria for Adverse Events (CTCAE) was used to assess the adverse events and liver dysfunction during and after the operation. RESULTS: Post treatment, 16 patients (16.2%) achieved CR and 59 (59.6%) achieved PR, the ORR was 75.8%. Subgroup analysis showed that patients with higher BCLC stage were of worse CR and ORR rates, and the CR as well as ORR between patients with cTACE history and patients without cTACE history were similar. Univariate logistic regression analysis displayed that number of nodules > 3, higher BCLC stage and previous cTACE might be correlated with worse ORR but with no statistical significance. As to liver function, CTCAE grades of laboratory indexes for liver function were increased at 1 week compared to baseline and recovered to the baseline grades at 1-3 months post operation. Besides, most of the common adverse events were light and moderate in our study. CONCLUSIONS: In conclusion, DEB-TACE by CalliSpheres® was efficient and well tolerated in Chinese HCC patients, and BCLC stage, number of nodules and cTACE history were possibly correlated with treatment response.

Identification, Characteristics and Mechanism of 1-Deoxy-N-acetylglucosamine from Deep-Sea Virgibacillus dokdonensis MCCC 1A00493.

Xanthomonas oryzae pv. oryzae, which causes rice bacterial blight, is one of the most destructive pathogenic bacteria. Biological control against plant pathogens has recently received increasing interest. 1-Deoxy-N-acetylglucosamine (1-DGlcNAc) was extracted from the supernatant of Virgibacillus dokdonensis MCCC 1A00493 fermentation through antibacterial bioassay-guided isolation. Its structure was elucidated by LC/MS, NMR, chemical synthesis and time-dependent density functional theory (TD-DFT) calculations. 1-DGlcNAc specifically suppressed X. oryzae pv. oryzae PXO99A (MIC was 23.90 µg/mL), but not other common pathogens including Xanthomonas campestris pv. campestris str.8004 and Xanthomonas oryzae pv. oryzicola RS105. However, its diastereomer (2-acetamido-1,5-anhydro-2-deoxy-d-mannitol) also has no activity to X. oryzae pv. oryzae. This result suggested that activity of 1-DGlcNAc was related to the difference in the spatial conformation of the 2-acetamido moiety, which might be attributed to their different interactions with a receptor. Eighty-four unique proteins were found in X. oryzae pv. oryzae PXO99A compared with the genome of strains8004 and RS105 by blastp. There may be unique interactions between 1-DGlcNAc and one or more of these unique proteins in X. oryzae pv. oryzae. Quantitative real-time PCR and the pharmMapper server indicated that proteins involved in cell division could be the targets in PXO99A. This research suggested that specificity of active substance was based on the active group and spatial conformation selection, and these unique proteins could help to reveal the specific mechanism of action of 1-DGlcNAc against PXO99A.

Coil and n-butyl-2-cyanoacrylate migration into the stomach after TIPS for gastroesophageal variceal bleeding: a case report and literature review.

BACKGROUND: Transjugular intrahepatic portosystemic shunt (TIPS) is a well-established therapeutic option for the management of variceal hemorrhage in patients with cirrhosis. The simultaneous migration of the coil and n-butyl-2-cyanoacrylate (NBCA) is an extremely rare but significant complication after TIPS. Because of its rare presentation, there are currently no definitive recommendations for the management of this condition. CASE PRESENTATION: A 46-year-old man with hepatitis B cirrhosis underwent TIPS placement for uncontrolled gastroesophageal varix (GEV) bleeding secondary to portal hypertension in August 2018. During the procedure, large GEVs were embolized using a coil and NBCA. After a year, coil and NBCA migration into the stomach was observed. Attempts to remove the coil using biopsy forceps during esophagogastroduodenoscopy failed. The patient refused further intervention on the coil to prevent further complications and received conservative therapy instead. Close surveillance with endoscopy is recommended for detecting coils and varices. CONCLUSIONS: The present case reports an extremely rare but significant complication after TIPS, which highlights the management and follow-up recommendation for such rare complications. Our experience may provide guidance for the management of future similar cases and stimulate discussion about treatment methods of similar patients.

Genome-wide screening reveals the genetic determinants of an antibiotic insecticide in Bacillus thuringiensis.

Thuringiensin is a thermostable secondary metabolite in Bacillus thuringiensis and has insecticidal activity against a wide range of insects. Until now, the regulatory mechanisms and genetic determinants involved in thuringiensin production have remained unclear. Here, we successfully used heterologous expression-guided screening in an Escherichia coli-Bacillus thuringiensis shuttle bacterial artificial chromosome library, to clone the intact thuringiensin synthesis (thu) cluster. Then the thu cluster was located on a 110-kb endogenous plasmid bearing insecticide crystal protein gene cry1Ba in strain CT-43. Furthermore, the plasmid, named pBMB0558, was indirectly cloned and sequenced. The gene functions on pBMB0558 were annotated by BLAST based on the GenBank(TM) and KEGG databases. The genes on pBMB0558 could be classified into three functional modules: a thuringiensin synthesis cluster, a type IV secretion system-like module, and mobile genetic elements. By HPLC coupling mass spectrometer, atmospheric pressure ionization with ion trap, and TOF technologies, biosynthetic intermediates of thuringiensin were detected. The thuE gene is proved to be responsible for the phosphorylation of thuringiensin at the last step by vivo and vitro activity assays. The thuringiensin biosynthesis pathway was deduced and clarified. We propose that thuringiensin is an adenine nucleoside oligosaccharide rather than an adenine nucleotide analog, as is traditionally believed, based on the predicted functions of the key enzymes, glycosyltransferase (ThuF) and exopolysaccharide polymerization protein (Thu1).

[Analyze and compare metabolic pathways of Bacillus cereus group].

A large number of data and information was obtained from genome sequencing and high-throughput genomic studies, use of the information to study metabolic networks become a new hotspot in biological research. This article compared different methods to reconstruct metabolic networks and analyzed the advantages and disadvantages of each methods, and then introduced some researches about carbohydrate metabolism pathways, amino acid metabolic pathways, and energy metabolism pathways of 9 strains of Bacillus cereus, 6 strains of B. anthracis,,6 strain of B. thuringiensis, and finds out their similarities and characteristics. These three strains have some necessary metabolic pathways, such as glycolysis, tri-carboxylic acid cycle, alanine metabolism, histidine metabolism, and energy metabolism, but they may have some specific pathways. B cereus has higher efficiency in utilizing monosaccharide, B. anthracis is rich in degradation and transport pathways of amino acids. A glutamate metabolic bypass way exists in B. thuringiensis. Analysis of metabolic pathways provides a new way to study and use food toxin, anthrax toxin, and insecticidal toxin of these strains in future.

Safety and efficacy of drug-eluting bead transarterial chemoembolization with CalliSpheres® microsphere for hepatocellular carcinoma with portal vein tumor thrombus: a preliminary study.

Objective: To prospectively evaluate the safety and therapeutic effectiveness of drug-eluting beads transcatheter arterial chemoembolization (DEB-TACE) with CalliSpheres® microsphere (CSM) for the treatment of hepatocellular carcinoma (HCC) with portal vein tumor thrombus (PVTT), and to analyze the prognostic factors. Method: Between November 2015 and November 2017, consecutive 58 HCC patients with PVTT who received DEB-TACE with CSM treatment were prospectively enrolled in this study. The demographic characteristics, adverse events (AEs) and treatment response were collected. Overall survival (OS) and progression-free survival (PFS) were calculated using the Kaplan-Meier method. Univariate and multivariate Cox regression analyses were performed to determine the independent factors correlated with OS. Results: The objective response rate (ORR) was 79.3% in terms of tumors and 44.8% in thrombi. The median PFS and OS of patients were 5.0 months and 9.0 months respectively. The cumulative survival rate at 3-, 6-, 9-, 12-, 18- and 24-month were 94.8%, 72.4%, 53.4%, 41.4%, 22.4% and 19.0%, respectively. In a stepwise multivariate Cox proportional hazards model, the higher Child-Pugh classification (HR=2.279; 95%CI, 1.042-4.985, p = 0.039) and tumor burden (p = 0.008) were the significant predictors of poorer OS after adjustment for known risk factors. The most common clinical AEs were postembolization syndrome (PES) and the most prevalent laboratory toxicity was transient liver function damage. Conclusion: DEB-TACE with CSM is safe and well-tolerated in HCC patients with PVTT, and reveals a favorable preliminary clinical outcome. The higher Child-Pugh classification and liver tumor burden are independent prognostic factors associated with poor survival for HCC patients with PVTT treated by DEB-TACE with CSM.

Complete Response of Hepatocellular Carcinoma with Macroscopic Vascular Invasion and Pulmonary Metastasis to the Combination of Drug-Eluting Beads Transarterial Chemoembolization and Huaier Granule: A Case Report.

BACKGROUND: Hepatocellular carcinoma (HCC) associated with macroscopic vascular invasion and distant metastasis is an advanced-stage disease with an extremely poor prognosis and low survival rate. Therefore, there is an urgent need to develop novel therapeutic strategies to extend the lives of patients with advanced HCC. CASE PRESENTATION: We represent a case of HCC with macroscopic vascular invasion and pulmonary metastasis responding dramatically to the combination treatment with drug-eluting beads transarterial chemoembolization (DEB-TACE) and Huaier granule. A 64-year-old man with hepatitis B virus (HBV)-induced liver cirrhosis was diagnosed with advanced HCC involved renal vein and inferior vena cava accompanied by pulmonary metastasis. The patient received three cycles of on-demand DEB-TACE from 9th September 2016 to 22nd August 2017 and combined with Huaier granule 20 g three times a day orally. Eight months following the treatment, complete response occurred with regression of HCC and vascular thrombus and disappearance of pulmonary metastasis. The levels of AFP had decreased from 8165.8ng/mL to within the normal range (1.7 ng/mL). This is the first case report of complete response of HCC to the combination treatment with DEB-TACE and Huaier granule. At the most recent follow-up, he remained in remission 36 months after cessation of treatment without clinical or imaging evidence of disease recurrence. The current overall survival is 54 months since the initial treatment. CONCLUSION: Data from this clinical case report suggest that the combination treatment with DEB-TACE and Huaier granule is a promising therapeutic option for advanced HCC with macroscopic vascular invasion and distant metastasis.

Comparison of Transjugular Intrahepatic Portosystemic Shunt in the Treatment of Cirrhosis With or Without Portal Vein Thrombosis: A Retrospective Study.

Aim: The purpose of our study was to conduct a retrospective analysis to compare the effectiveness of transjugular intrahepatic portosystemic shunts (TIPS) in the treatment of patients with cirrhosis with or without portal vein thrombosis (PVT). Methods: We included a total of 203 cirrhosis patients successfully treated with TIPS between January 2015 and January 2018, including 72 cirrhosis patients with PVT (35.5%) and 131 without PVT (64.5%). Our subjects were followed for at least 1 year after treatment with TIPS. Data were collected to estimate the mortality, shunt dysfunction, and complication rates after TIPS creation. Results: During the mean follow-up time of 19.5 ± 12.8 months, 21 (10.3%) patients died, 15 (7.4%) developed shunt dysfunction, and 44 (21.6%) experienced overt hepatic encephalopathy (OHE). No significant differences in mortality (P = 0.134), shunt dysfunction (P = 0.214), or OHE (P = 0.632) were noted between the groups. Age, model for end-stage liver disease (MELD) score, and refractory ascites requiring TIPS were risk factors for mortality. A history of diabetes, percutaneous transhepatic variceal embolization (PTVE), 8-mm diameter stent, and platelet (PLT) increased the risk of shunt dysfunction. The prevalence of variceal bleeding and recurrent ascites was comparable between the two groups (16.7 vs. 16.7% P = 0.998 and 2.7 vs. 3.8% P = 0.678, respectively). Conclusions: Transjugular intrahepatic portosystemic shunts are feasible in the management of cirrhosis with PVT. No significant differences in survival or shunt dysfunction were noted between the PVT and no-PVT groups. The risk of recurrent variceal bleeding, recurrent ascites, and OHE in the PVT group was generally similar to that in the no-PVT group. TIPS represents a potentially feasible treatment option in cirrhosis patients with PVT.

Adjuvant Transarterial Chemoembolization for Barcelona Clinic Liver Cancer Stage A Hepatocellular Carcinoma After Hepatectomy.

INTRODUCTION: The care for patients with hepatocellular carcinoma (HCC) is challenging. This study is to evaluate the effect of adjuvant transarterial chemoembolization (TACE) for Barcelona Clinic Liver Cancer (BCLC) stage A HCC patients after hepatectomy. METHODS: Consecutive HCC patients with BCLC stage A, treated by hepatectomy alone (HA) or hepatectomy with TACE (HT), were retrospectively enrolled. Propensity score matching (PSM) was used to balance baseline differences. The recurrence-free survival (RFS) and overall survival (OS) were evaluated using the Kaplan-Meier. The impact of TACE on survival outcome was determined by Cox hazard regression. RESULTS: After PSM, 230 patients (115 HT and 115 HA) were enrolled in the analysis. The 1-, 3-, and 5-year RFS rates were 87.0, 63.5, and 50.4%, respectively, for the HT group, and 87.8, 67.0, and 58.3% for the HA group. The OS rates at 1-, 3-, and 5-year were 99.1, 93.9, and 87%, respectively, for the HT group, and 100, 92.2, and 88.7% for the HA group. No significant differences were seen in either the RFS (log-rank test, χ2 = 0.891, p = 0.345) or OS (log-rank test, χ2 = 0.146, p = 0.702) between the specific pairs of two groups. Cox regression identified that TACE was not the factor affecting RFS or OS (p = 0.399; HR 0.847; 95% CI 0.576-1.245 for RFS vs. p = 0.989; HR 0.995; 95% CI 0.471-2.100 for OS). CONCLUSION: Our data indicate that TACE is not an effective intervention in the adjuvant setting for BCLC stage A HCC after hepatectomy.

Drug-eluting beads transarterial chemoembolization with CalliSpheres microspheres for treatment of unresectable intrahepatic cholangiocarcinoma.

Objective: This study aimed to evaluate the efficacy and safety of doxorubicin-loaded drug-eluting beads transarterial chemoembolization (DEB-TACE) with CalliSpheres microspheres (CSM) in treating unresectable intrahepatic cholangiocarcinoma (ICC). Methods: 88 unresectable ICC patients who received DEB-TACE treatment with CSM were retrospectively enrolled in this study. Information about treatment response, survival and adverse events were collected. The Kaplan-Meier curve was used to evaluate progression-free survival (PFS) and overall survival (OS), and factors affecting OS were determined by Cox's proportional hazards regression model. Results: Tumor response of the whole sample of 88 patients was partial response (PR) in 58 (65.9%) patients, stable disease (SD) in 19 (21.6%) and progressive disease (PD) in 11 (12.5%) at one month after therapy, with no complete responses (CR). The median PFS and OS were 3.0 months and 9.0 months respectively. Cox's proportional hazards regression analysis disclosed that subsequent treatment was an independent favorable prognostic factor, while cholangiectasis, extensive intrahepatic tumor burden and extrahepatic metastasis were the three prognostic factors associated with poor survival in ICC patients. Besides, common adverse events included nausea/vomiting, abdominal pain and transient elevation of liver transaminase in patients treated by DEB-TACE with CSM. Conclusion: DEB-TACE with CSM is safe and well-tolerated for unresectable ICC patients, with a low complication rate and a relative benefit in terms of survival. Subsequent treatments including systemic/loco-regional treatments is an independent favorable prognostic factor, but cholangiectasis, extensive intrahepatic tumor burden and extrahepatic metastases are the three prognostic factors associated with poor survival.

Gene Therapy with Cytosine Deaminase and Endostatin Fusion Gene Mediated by Endothelial Progenitor Cells in Hepatomas.

PURPOSE: Gene-targeting therapy provides a novel therapeutic approach for tumor treatment using genetically modified endothelial progenitor cells (EPCs) as cellular carriers. This study applied EPCs armed with cytosine deaminase (CD) and endostatin (ES) fusion gene in liver cancer to explore its therapeutic effect. MATERIALS AND METHODS: EPCs from heart blood of male BALB/c nude mice were cultured and transfected with CD and ES fusion gene. Subsequently, these genetically modified cells were injected into mice bearing hepatoma through their tail veins. The tumor volumes and cell apoptosis were followed up. RESULTS: Tumor volume in the group injected CD/ES-EPCs greatly decreased. The positive rate of VEGF and CD31 in the tumor tissue was lowest in the CD/ES-EPC group. Furthermore, the number of apoptotic cells was highest in the CD/ES-EPC group. CONCLUSION: The EPCs transfected with CD/ES inhibited tumor growth and preferentially induced tumor cell apoptosis, providing a novel methodology for cancer-targeting therapy.

Transcatheter embolization of hepatocellular carcinoma with epirubicin-loaded DC beads in Chinese patients.

BACKGROUND: This study evaluated the safety and efficacy of transcatheter chemoembolization with drug eluting beads (DEB-TACE) and compared it to the conventional TACE (cTACE) therapy method for hepatocellular carcinoma (HCC) in Chinese patients. METHODS: Seventy-four patients were treated with DEB-TACE using the DC bead, and 80 patients were treated with cTACE for HCC. The modified response evaluation criteria in solid tumors (mRECIST) criteria were used to evaluate clinical response, with adverse events assessed according to the Common Terminology Criteria for Adverse Events (CTCAE). RESULTS: Post-TACE, 9 patients (12.2%) achieved complete response (CR) and 44 (59.5%) achieved partial response (PR), with an overall tumor response rate (ORR) of 71.6% in the DEB-TACE group. Twelve patients (15%) achieved CR, and 38 (47.5%) achieved PR, with an ORR of 62.5% in the cTACE group. However, there was no significant difference in ORR between the two groups (P=0.229). Univariate logistic regression analysis determined that more than 3 nodules, higher Barcelona clinic liver cancer (BCLC) stage, portal vein invasion, previous chemotherapy (cTACE), and previous surgery were correlated with a worse ORR. Most common adverse events were not severe. CONCLUSIONS: DEB-TACE by DC bead was efficient and well-tolerated compared to cTACE in Chinese HCC patients. However, the present study showed no significant difference in ORR between the DEB-TACE and cTACE in the patient group with HCC. The BCLC stage, number of nodules, portal vein invasion, cTACE, and surgery history could possibly be a predictive factor for HCC treatment response.

Escherichia coli mismatch repair protein MutL interacts with the clamp loader subunits of DNA polymerase III.

It has been hypothesized that DNA mismatch repair (MMR) is coupled with DNA replication; however, the involvement of DNA polymerase III subunits in bacterial DNA MMR has not been clearly elucidated. In an effort to better understand the relationship between these 2 systems, the potential interactions between the Escherichia coli MMR protein and the clamp loader subunits of E. coli DNA polymerase III were analyzed by far western blotting and then confirmed and characterized by surface plasmon resonance (SPR) imaging. The results showed that the MMR key protein MutL could directly interact with both the individual subunits delta, delta', and gamma and the complex of these subunits (clamp loader). Kinetic parameters revealed that the interactions are strong and stable, suggesting that MutL might be involved in the recruitment of the clamp loader during the resynthesis step in MMR. The interactions between MutL, the delta and gamma subunits, and the clamp loader were observed to be modulated by ATP. Deletion analysis demonstrated that both the N-terminal residues (1-293) and C-terminal residues (556-613) of MutL are required for interacting with the subunits delta and delta'. Based on these findings and the available information, the network of interactions between the MMR components and the DNA polymerase III subunits was established; this network provides strong evidence to support the notion that DNA replication and MMR are highly associated with each other.

The key DNA-binding residues in the C-terminal domain of Mycobacterium tuberculosis DNA gyrase A subunit (GyrA).

As only the type II topoisomerase is capable of introducing negative supercoiling, DNA gyrase is involved in crucial cellular processes. Although the other domains of DNA gyrase are better understood, the mechanism of DNA binding by the C-terminal domain of the DNA gyrase A subunit (GyrA-CTD) is less clear. Here, we investigated the DNA-binding sites in the GyrA-CTD of Mycobacterium tuberculosis gyrase through site-directed mutagenesis. The results show that Y577, R691 and R745 are among the key DNA-binding residues in M.tuberculosis GyrA-CTD, and that the third blade of the GyrA-CTD is the main DNA-binding region in M.tuberculosis DNA gyrase. The substitutions of Y577A, D669A, R691A, R745A and G729W led to the loss of supercoiling and relaxation activities, although they had a little effect on the drug-dependent DNA cleavage and decatenation activities, and had no effect on the ATPase activity. Taken together, these results showed that the GyrA-CTD is essential to DNA gyrase of M.tuberculosis, and promote the idea that the M.tuberculosis GyrA-CTD is a new potential target for drug design. It is the first time that the DNA-binding sites in GyrA-CTD have been identified.

Identification and molecular characterization of novel cry1-type toxin genes from Bacillus thuringiensis K1 isolated in Korea.

To clone novel cry1-type genes from the Bacillus thuringiensis K1 isolate, about 2.4-kb-long PCR fragments were amplified with two primer sets of ATG1-F/N400-R and 1BeATG1-F/N400-R. Using PCR-RFLP, three novel cry1-type genes, cry1-1, cry1-7, and cry1-44, were obtained from B. thuringiensis K1 and the complete coding sequences of these novel genes were analyzed. The Cry1-1, Cry1-7, and Cry1-44 proteins showed maximum similarities of about 78.0%, 99.7%, and 91.0% with the Cry1Ha1, Cry1Be1, and Cry1Ac2 proteins, respectively. These novel cry1-type genes were expressed using a baculovirus expression vector system and their insecticidal activities were investigated. Whereas all three novel genes were toxic to Plutella xylostella larvae, only Cry1-1 showed insecticidal activity against Spodoptera exigua larvae.

[Isolation of endophytic antagonistic bacterium from Amorphophallus konjac and research on its antibacterial metabolite].

An endophytic antagonistic bacterium was isolated from Amorphophallus konjac calli. In order to identify this bacterium, 16S rDNA was amplified and partially sequenced. Sequence comparison showed that this sequence has the highest similarity to that in Bacillus subtilis, with 99.0% identities. That demonstrated this bacterium belongs to Bacillus subtili , named BSn5. The extracted extracellular protein from strain BSn5 had antibacterial activity against Erwinia carotovora subp. carotovora, which was unstable after heated, sensitive to proteinase K and resistant to trypsin. There was only a 31.6kDa protein component as by SDS-PAGE detection. Nondenaturing polyacrylaminde gel was used to purify this protein. The purified 31.6kDa protein exhibited inhibitory activity against Erwinia carotovora subp. carotovora. This protein is different from all known metabolites from Bacillus subtilis, suggesting that it may be a novel antibacterial protein.

[The plasmid harboring cry26Aa may contribute to the phenomenon of spore-crystal connection in Bacillus thuringiensis subsp. finitimus].

Parasporal crystal in B. thuringiensis subsp. finitimus T02 forms inside the exosporium and remains attached to the spore after mother cell lysis. Two crystal protein gene cry26Aa and cry28Aa were cloned from this strain. The relationship between the phenomenon of spore-crystal connection and the plasmids was investigated in this work. Mutants BMB1151 curing of the plasmid harboring cry26Aa, and BMB1152 curing of all plasmids were obtained from B. thuringiensis subsp. finitimus T02.The spore-crystal connection didn't appeared when cry26Aa and cry28Aa were transformed back into the strain BMB1152 by shuffle vector alone or in combination together. It suggested the plasmids of B. thuringiensis subsp. finitimus TD2 may contribute to the phenomenon. When gene cry26Aa was transformed back into in the strain BMB1151, spore-crystal connection didn't form either. So the plasmid harboring cry26Aa may also contribute to the phenomenon of spore-crystal connection in B. thuringiensis subsp. finitimus T02.

[Cloning and expression of nematicidal crystal protein gene cry6Aa of Bacillus thuringiensis].

On the basis of the sequencing of the N-terminal amino acid of the crystal protein, a nucleotide acid fragment harboring a novel nematicidal gene cry6Aa2 was obtained from Bacillus thuringiensis strain YBT-1518. This fragment contains two ORFs: orf1 and orf2, while a "stem-loop" exists between orf1 and orf2. BLAST showed the similarity of orf1 nucleotide acid sequence with cry6Aa1 is 98%, and has been deposited in the Genbank database (Acc. No. AF499736). The cloning fragment was transferred to crystal negative mutation strain BMB171 by E. coli-Bt shuttle vector pHT304. A 54kDa protein with similarity to strain YBT-1518 was detected in recombinant strain, and rice shaped crystal was detected with transmission electron microscope. Bioassay indicated the LC50 of recombinant strain against second lavae juvenile of Meloidgyne hapla is 9.47 microg/mL, nearly equal to the original strain YBT-1518 (10.74 microg/mL).

Archaeal communities in mangrove soil characterized by 16S rRNA gene clones.

An archaeal 16S rRNA gene library was constructed from mangrove soil. Phylogenetic analysis revealed archaea in mangrove soil including the Crenarchaeota (80.4%) and Euryarchaeota (19.6%) phyla. The archaeal community in mangrove soil appears to be a mixture of organisms found in a variety of environments with the majority being of marine origin.

[Cloning and functional analysis of the stable plasmid pBMB175 in Bacillus thuringiensis subsp. tenebrionis strains YBT-1765].

A 15.2 kb plasmid pBMB175 from Bacillus thuringiensis subsp. tenebrionis strains YBT-1765 was cloned and the restriction map was constructed. The mini-replicating region of pBMB175 was located in a 1151 bp fragment by functional analysis. The sequence of a 4152 bp fragment which contained the mini-replicating region was analyzed and results showed that the fragment had three potential open reading frames (ORF1, ORF2 and ORF3). Sequence comparison and homology search revealed that ORF1 (767AA) has 20% approximately 30% similarity to UvrD-helicase, RecD and RecB family proteins; no homology was found between ORF2 (149AA) and other known proteins; ORF3 shared 34% identification to a potential protein (ORF7) in pGI3. Deletion and sequence analysis presumed that the protein encoded by ORF2 maybe a new replication protein. Above all, pBMB175 likely belongs to a new plasmid family with a new replicon. The recombinant plasmid harboring the mini-replicating region is very stable, even after growth for more than 40 generations without selection, so it might be used as a cloning and expression vector.