Crystallization of the reaction center from Rhodobacter sphaeroides in a new tetragonal form

The reaction center from the nonsulfur purple bacteriumRhodobacter sphaeroideshas been crystallized in a new form. The crystals grew in the presence of polyethylene glycol 4000, the detergent β-octyl glucoside, and the amphiphiles heptane triol and benzamidine hydrochloride, using the sitting drop method. The space group of these crystals is tetragonal, P4₁(4₃)2₁2, and the cell constants are a = b = 141.5 Å and c = 276.7 Å with probably 2 proteins per asymmetric unit. A native data set has been set collected to a resolution of 2.8 Å consisting of 56,332 unique reflections (50,731 with F > 2σ) with anR_sym of 9.5%. Analysis of the diffraction data is underway using molecular and isomorphous replacement. © 1994 Wiley-Liss, Inc.     

Sodium hydroxide based non-detergent decellularizing solution for rat lung

Lung transplantation is the last option for the treatment of end stage chronic lung disorders. Because the shortage of donor lung organs represents the main hurdle, lung regeneration has been considered to overcome this hurdle. Recellularization of decellularized organ scaffold is a promising option for organ regeneration. Although detergents are ordinarily used for decellularization, other approaches are possible. Here we used high alkaline (pH12) sodium hydroxide (NaOH)-PBS solution without detergents for lung decellularization and compared the efficacy on DNA elimination and ECM preservation with detergent based decellularization solutions CHAPS and SDS. Immunohistochemical image analysis showed that cell components were removed by NaOH solution as well as other detergents. A Collagen and GAG assay showed that the collagen reduction of the NaOH group was comparable to that of the CHAPS and SDS groups. However, DNA reduction was more significant in the NaOH group than in other groups (p < 0.0001). The recellularization of HUVEC revealed cell attachment was not inferior to that of the SDS group. Ex vivo functional analysis showed 100% oxygen ventilation increased oxygen partial pressure as artificial hemoglobin vesicle-PBS solution passed through regenerated lungs in the SDS or NaOH group. It was concluded that the NaOH-PBS based decellularization solution was comparable to ordinal decellularizaton solutions and competitive in cost effectiveness and residues in the decellularized scaffold negligible, thus providing another potential option to detergent for future clinical usage.     

A Two-Step Procedure for Quantitative Isolation of Pure Double Strand DNA from Animal Tissues and Cell Cultures

A two step procedure for the quantitative isolation of protein- and RNA-free double-strand DNA from animal tissue and cell homogenates is described. In the first step proteins not complexed with DNA are hydrolyzed with an immobilized protease (Proteinase K) that is separated by filtration after the de-proteinization. Then the DNA is adsorbed to hydroxylapatite (HA) and desorbed from the adsorbent by stepwise elution with buffers of increasing ionic strength. The DNA content was determined directly from the absorption at 260 nm. The melting curve of the isolated DNA showed that it was double stranded. The protein content in the DNA was determined from the ratio of the adsorbance at 260 to 230 nm. Non-histone proteins complexed to DNA determined the rate of deproteinization that was found to be tissue specific. These proteins were found to have a larger influence on the ratio A₂₆₀/A₂₃₀ than histones, indicating that their absorption (at 230 nm) is markedly perturbed when they are bound to DNA.     

Absorption,Translocation and Adhering Capacities of Mycobacillin and Versicolin in Rice Plant Tissue

Mycobacillin adheres to the surface of seed or seedling but is not absorbed by rice plant tissue, whereas versicolin not only adheres to the surface but is also absorbed and subsequently translocated. The antibiotic re-extracted from the versicolin-treated plant tissue inhibits the growth of Helminthosporium oryzae. Thus mycobacillin is active only topically, while versicolin both topically and systemically.     

Partial recovery of cell membrane-bounded human interleukin-2 fusion protein from insect cell debris by using various detergent extractions

We previously found that the human interleukin-2 (hIL-2) fused with green fluorescent protein (GFP) mainly remained in the insect cell debris after disruption due to the highly hydrophobic property of hIL-2 itself. Even though the significant GFPuv/hIL-2 fusion proteins were associated with cell membrane fractions, these were still functionally active. Therefore, to increase the total product yield, we performed partial recovery of the cell membrane-bounded hIL-2 fusion protein from the insoluble cell debris using several non-ionic, zwitterionic, and anionic detergents.     

利用CHAPS分离豌豆叶绿体偶联因子复合物

近年来不少工作者对叶绿体偶联因子复合物的结构、功能和发生的问题颇为关注(程秋琛等 1986,Merchant等 1985,Nelson 1982,Pick等1979,Strontman等1983,Suss等 1983)。分离生物膜蛋白质的     

Microbial degradation of chelating agents used in detergents with special reference to nitrilotriacetic acid (NTA)

The extensive use of phosphate-based detergents and agricultural fertilizers is one of the main causes of the world-wide eutrophication of rivers and lakes. To ameliorate such problems partial or total substitution of phosphates in laundry detergents by synthetic, non-phosphorus containing complexing agents is practiced in several countries. The physiological, biochemical and ecological aspects of the microbial degradation of the complexing agents most frequently used, such as polyphosphates, aminopolycarboxylates (especially of nitrilotriacetic acid), and phosphonates are reviewed.Abbreviations AODC Acridine orange direct counts - ATMP Aminotrimethylphosphonate - DTPA Diethylenetriaminepentaacetate - DTPMP Diethylenetriaminepentamethylphosphonate - EDTA Ethylenediaminetetraacetate - EDTMP Ethylenediaminetetramethylphosphonate - ED3A Ethylenediaminetriacetate - HEDP Hydroxyethylidenediphosphonate - HEDTA Hydroxyethylethylenediaminetriacetate - IDA Iminodiacetate - IFT Immunofluorescence test - MW Molecular weight - NTA Nitrilotriacetate - PA Polyacrylate - PHC Polyhydroxycarboxylate - PMS Phenazine methosulfate - SDS-PAGE Sodium dodecylsulfate polyacrylamide gel electrophoresis - SPP Tetrasodiumpyrophosphate - STP Pentasodiumtriphosphate