A Translation Fusion Product of Two Different Insecticidal Crystal Protein Genes of Bacillus thuringiensis Exhibits an Enlarged Insecticidal Spectrum

Two truncated Bacillus thuringiensis crystal protein genes, belonging to the classes cryIA(b) and cryIC and both coding for insecticidal N-terminal fragments of the corresponding crystal proteins, were translationally fused. Expression of the gene fusion in Escherichia coli showed a biologically active protein with a toxicity spectrum that overlapped those of both contributing crystal proteins.     

大熊猫臼齿釉质的超微结构和氨基酸组成

大熊猫臼齿釉质的超微结构特征主要是施氏明暗带的宽度一般由8—15条釉柱组成;釉柱的横切面一般呈六角形或四角形,由里向外,釉柱的直径逐渐增大。在靠近釉牙本质界处,釉柱数量逐渐减少,有时甚至完全缺失,形成无釉柱结构的釉质。大熊猫臼齿釉质的氨基酸组成主要以甘氨酸,丙氨酸,谷氨酸,天冬氨酸和亮氨酸的含量为最高,而蛋氨酸,胱氨酸和酪氨酸的含量为最低。另外,还含有少量的羟脯氨酸。这种组成模式一般与人类和其它哺乳动物牙齿釉质的氨基酸组成相类似。     

The content and composition of the essential oil in the course of Anthodium development in wild camomile (Matricaria chamomilla L.)

A study was made of the changes in the content of essential oil and its components (farnesene, (-)-α-bisabolol, (-)-α-bisabololoxide A, (-)-α-bisabololoxide B and spathulenol, α-bisabolonoxide A, chamazulene, cis en-in-dicycloether) and of the number of secretory canals in the receptacles during the beginning of flowering, full flowering and the termination of flowering of camomile anthodia. The total content of the essential oil was highest during the beginning of flowering and lowest during its termination. The proportion of the individual sesquiterpenes in the essential oil underwent changes mostly during the beginning and termination of flowering. The number of secretory canals in the basal and middle anthodial parts increased during the beginning of flowering and the full flowering.     

Antifreeze protein produced endogenously in winter rye leaves

After cold acclimation, winter rye (Secale cereale L.) is able to withstand the formation of extracellular ice at freezing temperatures. We now show, for the first time, that cold-acclimated winter rye plants contain endogenously produced antifreeze protein. The protein was extracted from the apoplast of winter rye leaves, where ice forms during freezing. After partial purification, the protein was identified as antifreeze protein because it modified the normal growth pattern of ice crystals and depressed the freezing temperature of water noncolligatively.     

Two frameshift mutations in the cystic fibrosis gene

Cystic fibrosis (CF) is a recessive disease caused by mutations in the CF transmembrane conductance regulator (CFTR) gene. We have identified in exon 7 two frameshift mutations, one caused by a two-nucleotide insertion and the other caused by a one-nucleotide deletion; these mutations--CF1154insTC and CF1213delT, respectively, are predicted to shift the reading frame of the protein and to introduce UAA(ochre) termination codons at residues 369 and 368.     

Population density of aphids at the time of settling and ovariole maturation inCoccinella septempunctata [Col.: Coccinellidae]

In 1978 and 1979 in Central Bohemia the census of aphid populations on bean, sugar beet, cereals, maize, and alfalfa were taken at the time when overwinteredCoccinella septempunctata L. (1) settled and (2) the ovarioles of females ripened. Settling occurred immediately after aphid immigration. Minimum aphid density required for settling was estimated to about 10 aphids per 1 m² of field area. The aphid density at the time of ovariole ripening equaled 1 aphid per 200–400 cm² of leaf area.     

On preprocessing and antisymmetry in de novo peptide sequencing: improving efficiency and accuracy

Peptide sequencing plays a fundamental role in proteomics. Tandem mass spectrometry, being sensitive and efficient, is one of the most commonly used techniques in peptide sequencing. Many computational models and algorithms have been developed for peptide sequencing using tandem mass spectrometry. In this paper, we investigate general issues in de novo sequencing, and present results that can be used to improve current de novo sequencing algorithms. We propose a general preprocessing scheme that performs binning, pseudo-peak introduction, and noise removal, and present theoretical and experimental analyses on each of the components. Then, we study the antisymmetry problem and current assumptions related to it, and propose a more realistic way to handle the antisymmetry problem based on analysis of some datasets. We integrate our findings on preprocessing and the antisymmetry problem with some current models for peptide sequencing. Experimental results show that our findings help to improve accuracies for de novo sequencing.