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A series of 9 lactonic lipopeptide biosurfactants was isolated from Bacillus licheniformis IM 1307 as representatives of the lichenysin group and we propose to name them lichenysins G. They were recovered from the culture mediumas complex mixtures of molecules having different peptide sequences and different structures of /?-hydroxy fatty acids. Their separation was achieved by a reversed-phase HPLCmethod leading to eight well-separated compounds. The complete structure of individual isoforms was proposed following the results of amino acid and fatty acid analysis, LSI-MS and 2D NMRspectroscopies. Compared to surfactin, lichenysins G are at least 10 fold more efficient biosurfactants.

The processing of human collagen type-V chains was studied using anti-peptide polyclonal antibodies raised against peptide sequences at the N-terminal non-triple-helical region of pro-al(V) and pro-a2(V) chains. The anti-peptide polyclonal antibody raised against positions 48 -57 of the N-terminal a2(V) sequence recognized the mature form of the human a2(V) chain extracted without any proteolytic treatment from several tissues in the presence of a mixture of protease inhibitors. It also recognized the pro-a2(V) and pN-a2(V) collagen chains secreted in the cell-culture media of the rhabdomyosarcoma A204 cell line. The pN-a2(V) collagen chain from this cell line migrated during electrophoresis with the a2(V) chain obtained from tissues. This demonstrates that the a2(V) chain in tissues is incompletely processed and is present as the pN-a2(V) collagen chain which lacks the C-propeptide. In comparison, an anti-peptide polyclonal antibody raised against residues at positions 284-299 of the N-terminal al(V) human sequence failed to recognize the mature form of the al(V) chain while it reacted with the pN-al(V) collagen chain form. These results suggest that the al(V) chain undergoes a processing event in the N-terminal region that involves the removal of at least the first 284 residues.Amino acid sequence analysis was performed on cyanogen-bromide-generated or trypsin-generated peptides of the two electrophoretic bands obtained for the tissue form of collagen V. The slower-migrating band corresponding to the intact al(V) chain gave, as expected, only sequences corresponding to the al(V) chain. However, the band previously considered to be the intact a2(V) chain also gave sequences for the al(V) chain in addition to the a2(V) chain. This result indicates the presence in tissue extracts of a further processed form of al(V) chain which migrates with the intact a2(V) chain. On further analysis, we observed that the two bands of the tissue form of collagen V occurred in a 1 : 1 ratio whereas, after the pepsin digestion to remove non-collagenous regions, two bands were observed with an al(V)la2(V) chain ratio of 3 : 1. These results indicate that the a1 (V) chain exists in an additional stoichiometry, different from [al(V)],a2(V). We suggest the existence of two different populations of type-V collagen molecules consisting of an [a1 (V)],a2(V) heterotrimer bearing considerable N-terminal non-triple-helical extensions of both al(V) and a2(V) chains and an [al(V)], homotrimer composed of fully processed al(V) chains.Collagen V is a quantitatively minor constituent of collagen fibrils in the extracellular matrix, It is mainly found in tissues that contain type-I collagen as the major collagen component. Collagen V is heterogeneous and a1 (V)-a3(V)

Summary1. Molecular identification of animal or plant species in fresh and degraded products (e.g. food, faeces, hair and other organic remains) has become a very important issue in both conservation biology and food science. 2. In this proof-of-concept study, we developed a microarray-based method using cytochrome bderived probes to identify the main commercial and/or endangered vertebrate species in both food and forensic samples. 3. This method allowed the unambiguous identification of 71 out of 77 species tested. In the remaining six cases, identification was hampered due to false sequences deposited in GenBank and high intraspecific variability. Our evaluation of this DNA chip for routine control demonstrated its effectiveness for the simultaneous identification of at least five species, and that its sensitivity varied according to the type of sample analysed. 4. Synthesis and applications. Taken together, our results suggest that cyt b -based microarray is a reliable and powerful identification tool for vertebrates, and more generally highlights the significant role of both molecular and traditional taxonomy in the development of molecular identification methods.