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Six pure polychlorinated bornanes isolated from technical toxaphene, namely, Parlar 32 (toxicant B), Parlar 42a (toxicant A 1 ), Parlar 42b (toxicant A 2 ), Parlar 49a, Parlar 56, and Parlar 59, as well as the technical mixture were investigated as to their fate in a loamy silt under anaerobic conditions by laboratory studies taking 4 or 6 months. All test substances shared the geminal dichloro group in the C-2 position and, additionally, one chlorine atom each in the C-5 endo and C-6 exo positions, respectively. Reductive dechlorination was the major reaction leading to a sequential removal of a chlorine atom from each geminal dichloro group. Generally, in the first step of transformation, all six compounds lost a chlorine atom from the geminal dichloro group in the C-2 position, preferentially from the endo-position. The dechlorination rate was in the order of nonachlorobornanes > octachlorobornanes > heptachlorobornanes. While the two monodechlorination products formed from Parlar 32 underwent no further transformation, those products with additional geminal dichloro groups lost further chlorine atoms from exactly these groups. Finally, all six compounds formed two very stable end-metabolites in different ratios, which have been isolated and identified as 2-exo, 5endo,6-exo,8c,9b,10aand 2-endo,5-endo,6-exo, 8c,9b,10a-hexachlorobornane. Additionally, one of these end-metabolites was identified as the major product of the degradation of technical toxaphene after 6 months. † Dedicated to Prof. Dr. H.-D. Scharf on the occasion of his 65th birthday.

Despite the fact that almost 39% of the theoretical expressed proteins of Lactococcus lactis have a predicted isoelectric point above 7, these proteins have not been studied in previous proteome analyses. In the present study, we set up a reference map of alkaline lactococcal proteins by using immobilized pH gradients (IPG) spanning pH 6 to 12 and 9 to 12, and protein identification by matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS). Different electrophoresis systems for isoelectric focusing were evaluated to optimize the first dimension. Best results were obtained by sample application using cup-loading at the anodic side and increasing the final voltage up to 8000 V for IPGs, using N,N-dimethylacrylamide as monomer. After two-dimensional gel electrophoresis of extracts obtained from exponentially growing cells, about 200 protein spots were selected for identification by peptide mass fingerprinting. With MALDI-TOF MS, 153 proteins were identified that were the products of 85 different genes. Their predicted isoelectric points range from as high as 11.31 to as low as 6.34. Ribosomal proteins, hypothetical proteins and proteins with unknown function represent the largest groups of identified proteins. For further classification, the codon adaptation index (CAI) and grand average of hydropathicity (GRAVY) for each lactococcal protein were calculated. The protein with the lowest CAI identified in this study is the manganese ABC transporter ATP-binding protein. Less than 10% of the alkaline lactococcal proteins have a smaller CAI. The highest GRAVY for an identified protein is 0.26. The complete in silico data of Lactococcus lactis as well as clickable reference maps are available at www.wzw.tum.de/proteomik/lactis.

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