Efficient downsizing of peptides: By combination of two orthogonal “conformation‐based” and “sequence‐based” libraries, the cyclic pentapeptide cyclo(‐L‐Nal 1‐Gly 2‐D‐Tyr 3‐L‐Arg 4‐L‐Arg 5‐) (Nal=L‐3‐(2‐naphthyl)alanine; see overlay of the five lowest energy structures), which exhibited strong CXCR4 antagonism (IC50=4 nM) comparable to that of a 14‐residue lead compound, T140, was discovered.

Peptide auf das Wesentliche beschränkt: Das Pentapeptid cyclo(‐L‐Nal 1‐Gly 2‐D‐Tyr 3‐L‐Arg 4‐L‐Arg 5‐) wurde durch Kombination einer konformationsbasierten mit einer sequenzbasierten Peptid‐Bibliothek als möglicher CXCR4‐Antagonist ermittelt (Nal=L‐3‐(2‐Naphthyl)alanin; Bild: Projektion der fünf energetisch günstigsten Strukturen). Mit einem IC50‐Wert von 4 nM ist es vergleichbar effektiv wie die 14‐Aminosäuren‐Stammverbindung T140.

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A polyphasic taxonomic study was performed on Sphingomonas sp. strain RW1 T . The organism was isolated from water of the River Elbe and has been known as a potent metabolizer of dibenzo-p-dioxin and its relatives. TLC of a mild alkaline hydrolysate of extractable cellular lipids of strain RW1T and type strains of 21 Sphingomonas species gave a spot of sphingoglycolipid (SGL)-1 (glucuronosyl ceramide), which is characteristic of sphingomonads. In addition, strain RW1T and type strains of three Sphingomonas species (Sphingomonas yanoikuyae, Sphingomonas terrae and Sphingomonas macrogoltabidus) showed a second spot of SGL (SGL-1') identified as galacturonosyl ceramide. The presence of SGL-1 in cellular lipids suggested that strain RW1T is a member of the genus Sphingomonas. DNA-DNA reassociation rates between strain RW1 T and each type strain of 14 Sphingomonas species including Sphingomonas paucimobilis, type species for the genus, revealed that strain RW1 T is independent from these species. Results of phylogenetic analysis of 16S rDNA sequences of strain RW1T and type strains of 21 named Sphingomonas species verified that strain RW1 T belongs to the genus Sphingomonas. Strain RW1 T could be differentiated from named species of the genus by phenotypic characteristics and has been assigned to a new species, Sphingomonas wittichii sp. nov. The type strain is DSM 6014 T (l JCM 10273 T l EY 4224 T ). DNA GMC content is 67 mol %.

The immunodominant antigen A, IsaA, of Staphylococcus aureus was found to include a putative soluble lytic transglycosylase domain in its C-terminal region. Since the presence of this distinctive domain suggested that the protein might participate in peptidoglycan turnover, as indicated in Gram-negative bacteria, its cellular location was investigated. The protein was found not only in the culture supernatant but also in the cell wall fraction. To estimate its physiological role for the bacterium, its cell surface distribution was studied by immunoelectron microscopy. Protein A-gold particles binding to the immune complex were mainly located on the septal region of the bacterial cell surface. These data suggested that IsaA might be involved in bacterial cell separation through a preferential interaction with peptidoglycan chain.