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Abstract: The structural order of 1,4,9,10-naphthalene-tetracarboxylicacid-dianhydride (NTCDA) monolayers on Ag(111) has been investigated by spot profile analysis low energy electron diffraction (SPA-LEED). For increasing coverage, we find a sequence of three highly ordered structures: a commensurate structure (α), a uniaxially incommensurate structure (α2), and an incommensurate structure (β) with coverages of 0.9ML, 0.95ML, and 1 (saturated) monolayer (ML), respectively. In the high coverage regime, the structures coexist and a coverage increase causes a change of their relative fractions. The α and β structures were known before [U. Stahl, D. Gador, A. Soukopp, R. Fink, E. Umbach, Surf. Sci. 414 (1998) 423], but the β structure was proposed as commensurate, since its very small misfit with respect to a commensurate structure could not be resolved. This misfit leads to a periodic modulation, causing additional Moiré satellites in the diffraction pattern. This finding demonstrates the importance of high resolution methods for the geometry determination of large organic adsorbates. [Copyright &y& Elsevier]

All organisms have evolved several defence systems in order to protect themselves against bacteria, fungi and viruses. Higher organisms have developed a complex network of humoral and cellular responses, called adaptive immunity. A second defence system, innate immunity, was discovered in the early 1980s, consisting of small cationic peptides with a broad antimicrobial spectrum. These proteins act immediately at sites of infection or inflammation. The production of proteins with antimicrobial activity was not limited to higher organisms but was also found in insects, plants and microorganisms. During the last 2decades a broad range of proteins with very different structural features have been isolated and characterised from differing organisms ranging from bacteria to human beings. Over 500cationic membrane-acting proteins with antimicrobial and antifungal activities have been identified to date. Apart from these proteins, a very large number of antifungal proteins active on the fungal cell wall, on enzymes of the cell wall synthesis machinery, the plasma membrane and on intracellular targets have been characterised. [ABSTRACT FROM AUTHOR]

Examines the use of piezoresistive cantilevers with an atomic force microscope operating with a scanning electron microscope. Compatibility of the microscopes; Presentation of grating and integrated circuit images; Methods for the detection of lever deflection.

The purpose of this article is to review coculture fermentations in industrial biotechnology. Examples for the advantageous utilization of cocultures instead of single cultivations include the production of bulk chemicals, enzymes, food additives, antimicrobial substances and microbial fuel cells. Coculture fermentations may result in increased yield, improved control of product qualities and the possibility of utilizing cheaper substrates. Cocultivation of different micro-organisms may also help to identify and develop new biotechnological substances. The relevance of coculture fermentations and the potential of improving existing processes as well as the production of new chemical compounds in industrial biotechnology are pointed out here by means of more than 35 examples. [ABSTRACT FROM AUTHOR]

Investigates the processing effects on the nutritional advancement of probiotics and prebiotics. Efforts of health researchers to overcome difficulties that impact on the performance of functional foods; Importance of characterizing the interactions between probiotics and prebiotics in starter cultures or in functional foods prior to human consumption; Role of prebiotics on the viability and stability of probiotic cultures within food matrices during processing and storage.

l-glycerol 3-phosphate (l-G3P) was accumulated in Saccharomyces cerevisiae by pathway engineering. Intracellular concentration of this metabolic intermediate could be increased more than 20 times compared to the wild type by overexpressing GPD1 encoding the glycerol 3-phosphate dehydrogenase in a gpp1Δgpp2Δ mutant which lacks both isoenzymes of glycerol 3-phosphatase. Investigation of cellular pattern of triacylglycerols and glycerophospholipids did not reveal considerable changes due to accumulation of their precursor l-G3P. Hyperosmotic stress did not affect the l-G3P pool in the gpp1Δgpp2Δ mutant overexpressing GPD1 despite an about 4-fold increase of specific GPD activity. In contrast, oxygen limitation improved intracellular l-G3P concentration by enhancing the availability of cytosolic NADH. The reduction of pyruvate decarboxylase activity by deleting PDC2 led to an additional increase. In fact, the triple mutant gpp1Δgpp2Δ pdc2Δ overexpressing GPD1 accumulated 17 mg l-G3P/g dry weight during glucose batch fermentation under oxygen limitation. This value corresponds to an about 100-fold increase compared to that found in the wild type. [Copyright &y& Elsevier]