D-allulose-3-epimerase (DPEase) is the key enzyme for isomerization of D-fructose to D-allulose. In order to improve its thermal stability, short amphiphilic peptides (SAP) were fused to the N-terminal of DPEase. SDS-PAGE analysis showed that the heterologously expressed DPEase folded correctly in Bacillus subtilis, and the protein size was 33 kDa. After incubation at 40 °C for 48 h, the residual enzyme activity of SAP1-DSDPEase was 58%. To make the recombinant B. subtilis strain reusable, cells were immobilized with a composite carrier of sodium alginate (SA) and titanium dioxide (TiO2). The results showed that 2% SA, 2% CaCl2, 0.03% glutaraldehyde solution and a ratio of TiO2 to SA of 1:4 were optimal for immobilization. Under these conditions, up to 82% of the activity of immobilized cells could be retained. Compared with free cells, the optimal reaction temperature of immobilized cells remained unchanged at 80 °C but the thermal stability improved. After 10 consecutive cycles, the mechanical strength remained unchanged, while 58% of the enzyme activity could be retained, with a conversion rate of 28.8% achieved. This study demonstrated a simple approach for using SAPs to improve the thermal stability of recombinant enzymes. Moreover, addition of TiO2 into SA during immobilization was demonstrated to increase the mechanical strength and reduce cell leakage.
Bacillus subtilis/metabolism* ; Carbohydrate Epimerases/genetics* ; Enzyme Stability ; Enzymes, Immobilized/metabolism* ; Fructose ; Hydrogen-Ion Concentration ; Racemases and Epimerases ; Temperature

Larval excretory-secretory products of Anisakis simplex are known to cause allergic reactions in humans. A cDNA library of A. simplex 3rd-stage larvae (L3) was immunoscreened with polyclonal rabbit serum raised against A. simplex L3 excretory-secretory products to identify an antigen that elicits the immune response. One cDNA clone, designated as alpha-methylacyl CoA racemase (Amacr) contained a 1,412 bp cDNA transcript with a single open reading frame that encoded 418 amino acids. A. simplex Amacr showed a high degree of homology compared to Amacr orthologs from other species. Amacr mRNA was highly and constitutively expressed regardless of temperature (10-40degrees C) and time (24-48 hr). Immunohistochemical analysis revealed that Amacr was expressed mainly in the ventriculus of A. simplex larvae. The Amacr protein produced in large quantities from the ventriculus is probably responsible for many functions in the development and growth of A. simplex larvae.
Amino Acid Sequence ; Animals ; Anisakis/*enzymology/genetics ; Cloning, Molecular ; Cluster Analysis ; Gene Expression Profiling ; Gene Library ; Humans ; Immunohistochemistry ; Larva/enzymology/genetics ; Mice ; Mice, Inbred ICR ; Molecular Sequence Data ; Phylogeny ; Rabbits ; Racemases and Epimerases/genetics/*metabolism ; Sequence Homology, Amino Acid

OBJECTIVETo study the clinicopathologic features, differential diagnosis and prognosis of renal cell carcinoma associated with Xp11.2 translocations/TFE3 gene fusions.

METHODSThe histopathologic findings and immunophenotype of 11 cases of renal cell carcinoma associated with Xp11.2 translocations/TFE3 gene fusions were studied. Follow-up data (ranged from 10 to 112 months) were also analyzed.

RESULTSThere were a total of 7 females and 4 males. The age of patients ranged from 8 to 26 years (mean = 16.3 years). The diameter of the tumors varied from 2.5 to 6.0 cm. Histologically, two morphologic patterns were seen. The first pattern consisted of alveolar, papillary or nested architecture. The tumor cells contained voluminous, clear to eosinophilic cytoplasm, distinct cell borders, vesicular chromatin, and prominent nucleoli. Psammoma bodies were frequently found and could be abundant. In contrast, the second pattern was composed of nested and compact architecture. The tumor cells possessed less abundant cytoplasm and inconspicuous nucleoli. Few psammoma bodies were detected. Immunohistochemical study showed that all cases strongly expressed TFE3, CD10 and P504s. Variable positivity for pan-cytokeratin, epithelial membrane antigen and vimentin was also noted. None of them expressed CK7, Ksp-cadherin and CD117.

CONCLUSIONSRenal cell carcinoma associated with Xp11.2 translocations/TFE3 gene fusions is a newly described but rarely encountered subtype of renal cell carcinoma. Pathologic diagnosis can be established when taken age of the patients, histopathologic findings and immunoreactivity for TFE3 protein into consideration.

Adolescent ; Adult ; Basic Helix-Loop-Helix Leucine Zipper Transcription Factors ; metabolism ; Carcinoma, Renal Cell ; genetics ; metabolism ; Child ; Chromosomes, Human, X ; Female ; Follow-Up Studies ; Gene Fusion ; Humans ; Kidney Neoplasms ; genetics ; metabolism ; Male ; Neprilysin ; metabolism ; Racemases and Epimerases ; metabolism ; Translocation, Genetic ; Young Adult

OBJECTIVETo study the clinicopathologic features and immunophenotype of renal cell carcinomas, and to discuss their diagnostic value.

METHODSThe clinicopathologic features of 114 cases of renal cell carcinoma were reviewed and categorized on the basis of 2004 WHO classification. Immunohistochemical study for a panel of antibodies (including CK, CD10, vimentin, CD117, AMACR, CK7 and TFE3) was carried out. The follow-up data, if available, were also analyzed.

RESULTSThe cases were reclassified into 5 subtypes, including 77 cases (67.5%) of clear cell carcinoma (CCRCC), 11 cases (9.6%) of papillary renal cell carcinoma (PRCC), 14 cases (12.3%) of chromophobe renal cell carcinoma (chrRCC), 10 cases (8.8%) of renal carcinoma associated with Xp11.2 translocations/TFE3 gene fusions (Xp11.2RCC) and 2 cases (1.8%) of unclassified renal cell carcinoma (unRCC). Immunohistochemical study showed that the expression rates of CK, CD10 and vimentin in CCRCC were 93.5% (72/77), 93.5% (72/77) and 75.3% (58/77), respectively. On the other hand, all the 11 cases of PRCC studied were positive for AMACR. The expression rate of CD117 in chrRCC was 78.5% (11/14). In the 10 cases of Xp11.2 RCC studied, the expression rates of TFE3, AMACR, CD10 and CK were 100% (10/10), 100% (10/10), 90% (9/10) and 70% (7/10), respectively.

CONCLUSIONSThe various subtypes of renal cell carcinomas are heterogeneous in histologic appearance and demonstrate distinctive immunophenotype. The expressions of CD10, vimentin, CD117, AMACR, CK7 and TFE3 are helpful in the differential diagnosis.

Adenocarcinoma, Clear Cell ; pathology ; Adolescent ; Adult ; Aged ; Aged, 80 and over ; Basic Helix-Loop-Helix Leucine Zipper Transcription Factors ; genetics ; immunology ; metabolism ; Biomarkers, Tumor ; analysis ; genetics ; Carcinoma, Papillary ; immunology ; pathology ; Carcinoma, Renal Cell ; immunology ; metabolism ; pathology ; Female ; Gene Fusion ; Humans ; Immunophenotyping ; Kidney Neoplasms ; immunology ; metabolism ; pathology ; Male ; Middle Aged ; Neprilysin ; analysis ; Racemases and Epimerases ; analysis ; genetics ; Translocation, Genetic ; Vimentin ; analysis ; World Health Organization ; Young Adult