Analysis of the 2-keto-3-deoxyoctonate (KDO) region of lipopolysaccharides isolated from non-01 Vibrio cholerae 05R

Phosphorylated 2-keto-3-deoxyoctonate (KDO) has been detected in the strong-acid hydrolysates of lipopolysaccharides (LPS) of family Vibrionaceae including Vibrio cholerae. Structural analysis of LPS isolated from a rough mutant of non-01 V. cholerae 05 by dephosphorylation, periodate oxidation and methylation analysis revealed that the inner core region of the LPS molecule contains only one mole of KDO in contrast to enteric Gram-negative bacterial LPS, and that the phosphate group on the KDO molecule resides in the C4 position, while the site of binding of KDO to heptose, a constituent of the distal part of the inner core region, is the C5 position as in the enteric bacterial LPS.     

The barrier function of the outer membrane of Pseudomonas maltophilia in the diffusion of saccharides and β-lactam antibiotics

This paper reports that the efficiency of solute diffusion through the outer membrane of Pseudomonas maltophilia is roughly 3 to 5% of that of Escherichia coli. This is despite the fact that the outer membrane pore(s) is only a little smaller than that of E. coli. These results suggest that P. maltophilia has a low copy number of porin(s). The outer membrane of antibiotic resistant clinical isolates showed even less efficient permeability towards saccharides and antibiotics than the laboratory strains.     

Formation of a series of myo-inositol phosphates during growth of rice plant cells in suspension culture

A series of myo-inositol phosphates including myo-inositol mono-to hexa-phosphates was observed during growth of cultured riceplant cells. We also found that ³²Pi and myo-[2-³H] inositolwere incorporated into all these myo-inositol phosphates. myo-Inositolphosphorylating activity, which depended on ATP and Mg²⁺, wasdetected in the soluble fraction from the cells, and the reactionproduct was identified as myo-inositol-2-phosphate. (Received January 21, 1980; )     

Does the aquatic invertebrate nipple array prevent bubble adhesion? An experiment using nanopillar sheets

The nipple array is a submicrometre-scale structure found on the cuticle surfaces of various invertebrate taxa. Corneal nipples are an antiglare surface in nocturnal insects, but the functional significance of the nipple array has not been experimentally investigated for aquatic organisms. Using nanopillar sheets as a mimetic model of the nipple array, we demonstrated that significantly fewer bubbles adhered to the nanopillar surface versus a flat surface when the sheets were hydrophilic. Many more bubbles adhered to the hydrophobic surface than the hydrophilic surfaces. Bubbles on the body surface may cause buoyancy problems, movement interference and water flow occlusion. Here, bubble repellence is proposed as a function of the hydrophilic nipple array in aquatic invertebrates and its properties are considered based on bubble adhesion energy.     

Double-segment defining role of even-skipped homologs along the evolution of insect pattern formation

Recent studies on insect patterning suggest that the genetic hierarchy may be roughly conserved in phylogenetically divergent species, but pair-rule genes may not function identically in all insects. In order to understand potential evolutionary changes in the role of the pair-rule genes, a Bombyx even-skipped homolog was cloned and its expression pattern during early embryogenesis studied. Eight stripes of Bombyx even-skipped were progressively expressed in an antero–posterior order. Later, these stripes disappeared anteriorly. Under this detection system, Bombyx even-skipped stripes clearly do not resolve into the corre sponding secondary stripes, an obvious difference from Drosophila and Tribolium . These results suggest that Bombyx even-skipped may serve a double-segment defining role and may determine the odd-numbered engrailed stripes.     

Protein Synthesis during Neural and Epidermal Differentiation in Cynops Embryo

Two-dimensional gel electrophoresis was used to analyze protein synthesis in relation to neural and epidermal differentiation in Cynops pyrrhogaster embryo. Various regions of embryos at different developmental stages, from late morula to early neurula stages, were excised, radiolabelled with ³⁵S-methionine, and the pattern of protein synthesis were compared. The following four types of protein spots were observed: (1) six proteins synthesized characteristically in the epidermal region of the embryo after gastrulation, (2) two proteins synthesized in both epidermal and endodermal regions, but not in other regions, after gastrulation, (3) a protein first detected at early blastula stage, of which expression was nearly constant in presumptive epidermis region but declined in the other regions, (4) the candidate for neural plate specific protein synthesized at a very high level in ectoderm explants treated with concanavalin A, a substance which evokes neural induction.     

Characteristics of Yeasts Isolated from Pacific Crab Meat

A total of 202 cultures of yeasts were isolated and characterized from king crab and Dungeness crab meat. A yeastlike organism, resembling Aureobasidium pullulans, and 15 different species distributed among the genera Rhodotorula, Cryptococcus, Torulopsis, Candida, and Trichosporon were represented. Nine of the species grew at 5 C or lower. Although two of the species grew at 37 C, none of the isolates had the characteristics of pathogenic species. Members of the Cryptococcus and Candida failed to grow at 37 C. Furthermore, species of the former genus were not pathogenic to mice. The pigmentation of the Rhodotorula cultures decreased in intensity as the incubation temperature was decreased. Biochemical activities of the different species were studied by use of triglycerides, lecithin, and proteins (casein, gelatin, and crab-meat protein) as substrates. Eight of the species could attack triglycerides; eight, lecithin; five, gelatin; one, casein; and one, crab protein. An organism, tentatively identified as Trichosporon sp., was very active in attacking each of the substrates tested and grew well at 0.5 C.