Amino acid sequence of alpha-subunit in hen egg white ovomucin deduced from cloned cDNA.

The primary amino acid sequence of alpha-subunit in ovomucin (OVM) from hen thick egg white was determined. The 2087 amino acid residues with a relative molecular mass of 230.9 kDa along the full length of the alpha-subunit were represented. The alpha-subunit contains domains, arranged from the N- to C-terminals in the following order: D1-D2-D'-D3-R (central region)-D4-C1-CK (Cystine-knot), in a manner similar to the arrangement of D, C and CK domains in human pre-pro-von Willebrand factor (hpp-vWF) and hMUC2. The alpha-subunit showed identities on amino acid sequences with hpp-vWF and hMUC2 at 33 and 41% in the N-terminal region and 30 and 38% in the C-terminal region, respectively. The numbers and positions of cysteine residues were highly conserved among alpha-subunit, hpp-vWF and hMUC2. However, R showed no virtual sequence homology with the corresponding regions in two proteins. It was estimated that alpha-subunit was not part of a large peptide of OVM, but was independently synthesized from beta-subunit.

Development of a novel polyimide hollow-fiber oxygenator.

We have developed a membrane oxygenator using a novel asymmetric polyimide hollow fiber. The hollow fibers are prepared using a dry/wet phase-inversion process. The gas transfer rates of O(2) and CO(2) through the hollow fibers are investigated in gas-gas and gas-liquid systems. The polyimide hollow fiber has an asymmetric structure characterized by the presence of macrovoids, and the outer diameter of the hollow fiber is 330 microm. It is found that the polyimide hollow-fiber oxygenator can enhance the gas transfer rates of O(2) and CO(2), and that the hollow fiber provides excellent blood compatibility in vitro and in vivo.

Surface modification of poly(L: -lactic acid) affects initial cell attachment, cell morphology, and cell growth.

The object of this study was to develop a highly porous scaffold to be used in regeneration of blood vessels, nerves, and other hollow tissues with small openings. Using the phase-inversion method and a mixture of water and methanol as a coagulating agent, we prepared highly porous flat membranes from poly(L: -lactic acid) (PLLA) with numerous pores both on the surface and in the interior of the membranes. Chinese hamster ovary (CHO) cells were cultured on the membranes to evaluate initial cell adhesion, cell proliferation, and cell morphology. Adhesion of CHO cells to PLLA was poor: the cells adhered at approximately half the rate observed with a tissue culture polystyrene dish (TCPS). In contrast, adhesion of cells to PLLA treated with a low-temperature oxygen plasma was good; the adhesion rate was the same as that on TCPS. The rate of cell proliferation on the treated membranes was no different from that on the nontreated membranes, but cell morphologies were quite different. The cells on the nontreated membranes were small and round and proliferated separately from one another. In contrast, the cells on the plasma-treated membranes proliferated in close contact with other cells, spreading out extensively in sheet-like formations. Since the plasma treatment not only accelerated cell adhesion but also enabled cells to proliferate in the form of sheets resembling biological tissue, we believe that oxygen-plasma treatment is extremely effective for modifying surfaces of materials used for tissue regeneration.

Alicyclobacillus acidiphilus sp. nov., a novel thermo-acidophilic, omega-alicyclic fatty acid-containing bacterium isolated from acidic beverages.

A novel thermo-acidophilic bacterium was isolated from an acidic beverage that had the odour of guaiacol. The cells are aerobic, gram-positive, spore-forming rods. The organism, strain TA-67T, grows at temperatures from 20 to 55 degrees C (optimum, 50 degrees C) and at pH values from 2.5 to 5.5 (optimum, pH 3.0). It possesses omega-cyclohexane fatty acid as a major cellular fatty acid. The G+C content of the DNA is 54.1 mol%. Phylogenetic analysis of the 16S rRNA gene sequences indicated that strain TA-67T constituted a distinct lineage in the Alicyclobacillus cluster, with Alicyclobacillus acidoterrestris as the closest neighbour (96.6% homology). Phenotypically, it is similar to, but can be distinguished from, omega-cyclohexane fatty acid-possessing alicyclobacilIi (A. acidoterrestris, Alicyclobacillus acidocaldarius, Alicyclobacillus hesperidum and 'Alicyclobacillus mali') by the morphology of spores and sporangia, by the growth response to different temperatures, and by the profiles for acid production from carbon sources. It is the alicyclobacillus that produces guaiacol, a causative substance for an 'off' flavour of orange juice. On the basis of the phenotypic and phylogenetic evidence, it is concluded that strain TA-67T represents a new species of the genus Alicyclobacillus, for which the name Alicyclobacillus acidiphilus is proposed. The type strain is TA-67T (= DSM 14558T = IAM 14935T = NRIC 6496T).

Alicyclobacillus herbarius sp. nov., a novel bacterium containing omega-cycloheptane fatty acids, isolated from herbal tea.

A thermo-acidophilic gram-positive bacterium, strain CP-1T, which grows aerobically at 35-65 degrees C (optimum 55-60 degrees C) and at pH 3.5-6.0 (optimum pH 4.5-5.0), was isolated from a herbal tea made from the dried flowers of hibiscus. Phylogenetic analysis of the 16S rRNA gene sequences showed that this bacterium was clearly distinguishable from previously described species of the genera Alicyclobacillus and Sulfobacillus. Strain CP-1T had unique omega-cycloheptane fatty acids as the major membrane lipid component, a characteristic which is peculiar to Alicyclobacillus cycloheptanicus. However, phenotypic and chemotaxonomic characteristics of strain CP-1T were different from those of the type strain of A. cycloheptanicus. DNA-DNA hybridization between the type strains of Alicyclobacillus species and Sulfobacillus disulfidooxidans was <20%, indicating that strain CP-1T represents a distinct species. On the basis of these results, the name Alicyclobacillus herbarius is proposed for this organism. The type strain is strain CP-1T (= DSM 13609T = IAM 14883T = NRIC 0477T).