Panos, Charles (University of Illinois College of Medicine, Chicago, and Albert Einstein Medical Center, Philadelphia, Pa.). Streptococcal L-forms. IV. Comparison of the metabolic rates of a Streptococcus and derived L-form. J. Bacteriol. 84:921-928. 1962.-Glycolytic rates of hexoses, amino sugars, pentoses, two-carbon compounds, and certain intermediates of glycolysis and the adaptive response to glucose of a group A Streptococcus and its derived L-form were compared. It was found that removal of the streptococcal cell wall did not result in the loss of the homolactic characteristic of the parent coccus or in a marked increase in the metabolism of certain glycolytic intermediates by the L-form. It was shown that (i) a major difference exists between the coccus and its L-form in the metabolism of glucosamine and N-acetylglucosamine; (ii) apparently, a loss of selectivity and internal control occurred in the transformation to the L-form; and (iii) this form, unlike the parent coccus, displayed an adaptive response to glucose. These data were not the result of an internal loss of essential cofactors or enzymes by diffusion from within the L-form. Nor could they be accounted for by dry-weight differences due to loss of the streptococcal cell wall. Finally, it was observed that the sonically disintegrated L-form in 0.5 m NaCl was capable of a glycolytic activity of 46% of that of the total intact culture. These data suggest that the conversion of a streptococcus to the L-form is accompanied by an alteration in carbohydrate metabolism as well as the loss of the cell wall. Previously reported data are in agreement with these findings and support the conclusion that the resulting form is not merely a bacterial cell without a rigid cell wall.

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PubMed1962

STREPTOCOCCAL L FORMS V. : Acid-Soluble Nucleotides of a Group A Streptococcus and Derived L Form.

Edwards, John (University of Illinois College of Medicine, Chicago, and Albert Einstein Medical Center, Philadelphia, Pa.) and Charles Panos. Streptococcal L-forms. V. Acid-soluble nucleotides of a group A Streptococcus and derived L form. J. Bacteriol. 84:1202-1208. 1962.-This report deals with a comparison of the acid-soluble nucleotides from a group A, type 12, beta-hemolytic streptococcus and a derived stable L form. This is the first report of the presence of a cell-wall precursor (uridine diphosphate-muramic acid-peptide) in a stable L form. Cells of each organism were obtained during their logarithmic phases of growth, harvested by centrifugation, and washed with osmotically protective NaCl solutions. The analytical procedures were essentially those of Franzen and Binkley. Calculated values indicated that these results could not be accounted for by dry-weight differences due to loss of the streptococcal cell wall. It was found that both organisms contained the same amount of total nucleotide material. The L form contained no uridine monophosphate (UMP), a large concentration of uridine diphosphate (UDP)-muramic acid-peptide, and a significant increase of UDP-N-acetylglucosamine. A similar nucleotide containing muramic acid-peptide was not demonstrable in the parent coccus. Instead, UMP and an unidentified uridine nucleotide were resolved in this region. Analyses of extracts from this streptococcal L form indicate the probable presence of two of the three nucleotides originally isolated by Park from penicillin-treated Staphylococcus aureus. The presence of the UDP-muramic acid-peptide cell-wall precursor in the L form cultured in the continual absence of penicillin points to an inability of this form to resynthesize the rigid cell wall and indicates that this synthetic mechanism has been permanently impaired.

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