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1.  Biological activities of pyochelins: iron-chelating agents of Pseudomonas aeruginosa. 
Infection and Immunity  1978;22(3):878-890.
Strains of Pseudomonas aeruginosa able to grow readily in serum (serum resistant) produce siderophores in large quantity, enabling them to extract iron from transferrins. The term pyochelin has been proposed for this group of compounds. Pyochelin extractable with ethyl acetate and designated pyochelin A appears to be a mixture of catechols and other phenolates. The structures of water-soluble siderophores, designated pyochelin B, have not been determined. Pyochelins enabled growth in serum of strains of serum-sensitive P. aeruginosa and other gram-negative bacilli. Serum-resistant strains of P. aeruginosa tended to be more virulent than equally toxigenic strains of the serum-sensitive group. However, incorporation of pyochelins into the inocula of serum-sensitive strains could reduce, rather than enhance, their virulence. Utilization of pyochelins by serum-sensitive strains of P. aeruginosa rendered some of these organisms resistant to pyocins which were otherwise lethal to them.
PMCID: PMC422240  PMID: 103839
2.  Pharmacological Evaluation of Cefaclor in Volunteers 
The plasma and urine concentrations of cefaclor were measured after oral administration of single and multiple doses to volunteers. Cefaclor was rapidly absorbed, rapidly excreted in the urine, well tolerated without toxicity, and failed to accumulate in the plasma with chronic dosing.
PMCID: PMC352480  PMID: 708022
3.  PR toxin production in different Penicillium roqueforti strains. 
Different Penicillium roqueforti strains from the American Type Culture Collection were tested for the production of PR toxin. All four strains were able to produce the toxin on semisynthetic medium at 24 degrees C after certain periods of incubation. The yields were correlated with the pH of the medium. Timing of the harvest influenced both the yield and purification of the toxin.
PMCID: PMC242925  PMID: 25626
4.  Cell-free biosynthesis of the O-acetylated N-acetylneuraminic acid capsular polysaccharide of group C meningococci. 
Journal of Bacteriology  1978;133(3):1300-1306.
A cell-free system was established to study the biosynthesis of group C meningococcal capsular polysaccharide, an alpha-2 leads to 9-linked N-acetylneuraminic acid (NeuAc) homopolymer containing O-acetyl groups at either C7 or C8. Sialyltransferase activity, isolated from group C meningococcus strain C-11, catalyzed incorporation of [14C]NeuAc from CMP (CMP--[14C]NeuAc) into polymeric form. This sialyltransferase was stimulated by addition of meningococcus group C and Escherichia coli K92 capsular polysaccharides, the latter being an alpha-2 leads to 8- and alpha-2 leads to 9-linked NeuAc heteropolymer. Group C meningococcal sialyltransferase did not require divalent ions but was stimulated by Mn2+. Attempts to demonstrate a lipid-soluble intermediate in the biosynthesis of this NeuAc polymer were unsuccessful. Meningococcal group C sialyltransferase incorporated NeuAc into a membrane-associated product. The polysaccharide can be extracted from the membrane-bound fraction with Triton X-100. The newly synthesized polysaccharide coprecipitates with authentic group C antigen in meningococcal group C antiserum and is degraded by sodium metaperiodate, indicating that the NeuAc polymer synthesized by the cell-free system consists of alpha-2 leads to 9 linkage. Meningococcal group C spheroplast membranes contain an O-acetylase that can catalyze the transfer of acetyl groups from acetyl coenzyme A to the in vitro-synthesized polysaccharide.
PMCID: PMC222166  PMID: 25263
5.  Characterization of an immunoglobin cDNA clone containing the variable and constant regions for the MOPC 21 kappa light chain. 
Nucleic Acids Research  1978;5(9):3101-3111.
Nucleotide sequence analysis and restriction endonuclease mapping have been used to characterize a cDNA copy of immunoglobulin MOPC 21 Kappa mRNA clones in the bacterial plasmid pMB9. Three regions of the inserted cDNA of plasmid pL21-1 have been sequenced and match the known protein sequence at amino acid residues 1-24, 128-138 and 171-179. With these sequences to provide absolute correlations between the restriction map and the structural gene sequence it has been possible to exactly deduce the positions of all 11 of the insert restriction sites mapped within the structural gene. The pL21-1 insert contains the complete variable and constant regions as well as parts of the 3' untranslated and polypeptide leader coding sequences.
PMCID: PMC342234  PMID: 100766

Results 1-5 (5)