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Since the sulfur specific cleavage is vital for the organic sulfur removal from fossil fuel, we explored potential bacterial strains of MTCC (Microbial Type Culture Collection) to desulfurize the Dibenzothiophene (DBT) through C-S bond cleavage (4-S pathway). MTCC strains Rhodococcus rhodochrous (3552), Arthrobacter sulfureus (3332), Gordonia rubropertincta (289), and Rhodococcus erythropolis (3951) capable of growing in 0.5 mM DBT were examined for their desulfurization ability. The presence of dsz genes as well as the metabolites was screened by polymerase chain reaction (PCR) and HPLC, respectively. All these strains showed > 99% DBT desulfurization with 10 days of incubation in minimal salt medium. From the HPLC analysis it was further revealed that these MTCC strains show differences in the end metabolites and desulfurize DBT differently following a variation in the regular 4-S pathway. These findings are also well corroborating with their respective organization of dszABC operons and their relative abundance. The above MTCC strains are capable of desulfurizing DBT efficiently and hence can be explored for biodesulfurization of petrochemicals and coal with an eco-friendly and energy economical process.

The 0-specific moieties of the O1B antigen (lipopolysaccharide) from Escherichia coli O1B:K1 and the O1C antigen from E. coli O1C:K-both consist of L-rhamnose, D-galactose, N-acetyl-D-glucosamine, and N-acetyl-D-mannosamine in a molar ratio of 2:1:1:1. By using fragmentation procedures, methylation analysis, and oneand two-dimensional nuclear magnetic resonance spectroscopy, the structures of these polysaccharides were found to beIn the O1B polysaccharide X is 2, and in the O1C polysaccharide X is 3. With the recently published structure of the OlA polysaccharides (B. Jann, A. S. Shashkov, D. S. Gupta, S. M. Panasenko, and K. Jana, Carbohydr. Polym. 18:51-57 1992), three related 01 antigens are now known. Their common (01-specific) epitope is suggested to be the side-chain N-acetyl-D-mannosamine residue.Escherichia coli strains that express the 01 antigen (lipopolysaccharide [LPS]) and the Kl antigen (capsular polysaccharide) are known to cause extraintestinal infections in humans (20,23,25,29,30). An analysis of extraintestinal E. coli (1, 17, 23) on the basis of sodium dodecyl sulfateMost of the strains were of the 01:K1 serotype and expressed LPSs with two related SDS-PAGE patterns, which were termed O1A and OlAl LPSs. Three strains expressed an LPS with a different SDS-PAGE pattern, which was termed 01B. Another strain had yet another LPS, termed

The 0-specific polysaccharide moieties (PS) of the 018A, 018A1, 018B, and 018B1 antigens (lipopolysaccharides, LPS) consist of L-rhamnose (Rhd), N-aCetyl-D-glUCOSamine, D-galaCtOSe, and D-glucose in different molar ratios. By using chemical fragmentation, methylation, as well as oneand two-dimensional NMR spectroscopy, the structures of these polysaccharides were found to beIn 018A-PS and 018A1-PS x = 2, whereas in 018B-PS and in 018B11-PS x = 3. In all fourGlcpNAc-(1 in 018A-PS and 018A1-PS and it is a-~-Glcp-(l in 018B-PS and 018B1-PS. Whereas there is no further substituent on the main chain of the 018A and 018B polysaccharides, in 018A1-PS and 018B1-PS the E-D-GIc~NAc residue A is substituted with a-Glcp-(1 (residue F), which is linked to 0 -6 in 018A1-PS and to 0 -4 in 018B1-PS. These results show that the 018 antigen comprises a group of four related LPS (018A and OIXB, with their glucosylated forms 018A1 and 01 SBl). The results are discussed with respect to epitope definition and biochemical implications.The serological classification of Escherichiu coli is based on their 0 antigens (lipopolysaccharides, LPS), K antigens (capsular polysaccharides), H antigens (flagellar proteins) [I -31 and, more recently also on their F antigens (fimbrial and fibrillar proteins) [4]. Additionally, such distinctive characteristics as biotype or isoenzyme pattern as detected by starch gel electrophoresis [5] are in use. In a clonal analysis of E. coli, strains with 0 antigens prevalent in extraintestinal infections, emphasis was put on the migration patterns of the major outer membrane proteins in sodium dodecyl sulfate/polyacrylamide gel electrophoresis (SDS/PAGE) [6]. In these and subsequent studies 17-91, it became apparent that many strains, even when belonging to different E. coli clones, were of the same 0 group. This was particularly evident with E. coli expressing the 0 1 or the 018 antigen. On the basis of their migration patterns in SDS/PAGE, the 01 antigens were divided into three groups (OIA, 01B and OlC). Of these, the 0 1 A antigen seemed to be clonally restricted, whereas no clonality of the 0 1 B and 0 1 C (only one strain known) was detected with the same method. The 018 antigens which had been serologically classified into 018ac and 018ab [lo] were subdivided into Abbreviations. 2D COSY, two-dimensional correlated NMR spectroscopy; LPS, lipopolysaccharide; PS, polysaccharide moiety of lipopolysaccharide; TOE, truncated driven mode of nuclear Overhauser effect (NOE) NMR experiment; Rha, rhamnose. four groups 171. They were termed 018A and 018A1 (formerly 018ac) and 018B and 018B1 (formerly 018ab).Serological studies showed that the 018 antigens shared (at least) one epitope and were otherwise distinct.To establish a molecular basis for the observed 0 antigen differences, we have set out to elucidate the structures of the respective LPS. Recently, we reported the structures of the 01A, 01B and 01C LPS [ll, lla]. In an earlier report we presented the structure of the 018ac LPS [12], which is now defined as...

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