A monoclonal antibody obtained by immunization of mice with heat-killed cells of Listeria monocytogenes serotype 4d showed reactivity towards a protein (P45) from L. monocytogenes with an apparent molecular mass of 45 kDa. This protein was detected in the culture supernatant and at the cell surface of L. monocytogenes. Proteins cross-reacting with the monoclonal antibody were present in all Listeria strains investigated, except L. grayi. The structural gene was cloned in Escherichia coli and sequenced. Translation of the gene starts at a TTG initiation codon. The gene was found to code for a protein of 402 amino acid residues with a predicted molecular mass of 42.7 kDa. It has a signal peptide of 27 amino acid residues, resulting in a molecular mass for the mature polypeptide of 39.9 kDa. Protein database searches showed that this protein has 55% similarity and 38% identity to protein p60 of L. monocytogenes and exhibits significant sequence similarities to p54 from Enterococcus faecium and Usp45 from Lactococcus lactis. P45 was shown to have peptidoglycan lytic activity and the encoding gene was named spl (secreted protein with lytic property).

No abstract

No abstract

Lipoteichoic acids were isolated from eleven species of the genus Staphylococcus using phenol-water partition and hydrophobic chromatography on octyl-Sepharose CL-4B. The lipoteichoic acids purified could be visualized by SDS-PAGE. They were shown to be composed of a hydrophilic poly(glycerophosphate) chain covalently linked to gentiobiosyldiacylglycerol, the common lipid anchor of these molecules. Glycerophosphate units of the hydrophilic chain were found to be partly substituted with ester-linked D-alanine, except in the case of S. cohnii. The lipoteichoic acids isolated from S. cohnii, S. hominis, S. saprophyticus and S. simulans contain alpha(1-2)-linked N-acetylglucosamine as an additional substituent of the poly(glycerophosphate) backbone.

Net secretion rate of para-aminohippurate (PAH) in the proximal convolution of the rat kidney changes concomitantly with single nephron glomerular filtration rate (GFR) and intratubular flow rate. Reabsorption of PAH in the proximal convolution is negligible. The PAH concentration profile along the length of the proximal convolution does not change markedly with variations in GFR. Net PAH secretion by single nephrons, measured at the end of proximal convolutions, is about one-half that measured at the beginning of distal convolutions and in final urine. As in the entire kidney, at constant renal plasma flow and concentration of PAH, renal secretion rate of PAH also changes concomitantly with GFR. It is concluded that PAH secretion along the loop of Henle (i.e., probably along the pars recta) is also related to single nephron GFR, as is PAH secretion in the proximal convolution.