title: Influence of temperature of incubation and type of growth medium on pigmentation in Serratia marcescens.
abstract: Maximal amounts of prodigiosin were synthesized in either minimal or complete medium after incubation of cultures at 27 C for 7 days. Biosynthesis of prodigiosin began earlier and the range of temperature for formation was greater in complete medium. No prodigiosin was formed in either medium when cultures were incubated at 38 C; however, after a shift to 27 C, pigmentation ensued, provided the period of incubation at 38 C was not longer than 36 hr for minimal medium or 48 hr for complete medium. Washed, nonpigmented cells grown in either medium at 38 C for 72 hr could synthesize prodigiosin when suspended in saline at 27 C when casein hydrolysate was added. These suspensions produced less prodigiosin at a slower rate than did cultures growing in casein hydrolysate at 27 C without prior incubation at 38 C. Optimal concentration of casein hydrolysate for pigment formation by suspensions was 0.4%; optimal temperature was 27 C. Anaerobic incubation, shift back to 38 C, killing cells by heating, or chloramphenicol (25 mug/ml) inhibited pigmentation. Suspensions of washed cells forming pigment reached pH 8.0 to 8.3 rapidly and maintained this pH throughout incubation for 7 days. Measurements of viable count and of protein, plus other data, indicated that cellular multiplication did not occur in suspensions of washed cells during pigment formation. By this procedure utilizing a shift down in temperature, biosynthesis of prodigiosin by washed cells could be separated from multiplication of bacteria.
mesh_terms: D000900:Anti-Bacterial Agents / Q000096:biosynthesis*; D001426:Bacterial Proteins / Q000096:biosynthesis; D001431:Bacteriological Techniques; D002364:Caseins; D002455:Cell Division; D002701:Chloramphenicol / Q000494:pharmacology; D003470:Culture Media; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D010100:Oxygen; D010860:Pigments, Biological / Q000096:biosynthesis*; D011353:Prodigiosin / Q000096:biosynthesis; D011492:Protein Hydrolysates; D011758:Pyrroles / Q000096:biosynthesis*; D012440:Saccharomyces; D012706:Serratia marcescens / Q000166:cytology / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*; D013053:Spectrophotometry; D013696:Temperature; D013997:Time Factors
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D002364:Caseins; D003470:Culture Media; D010860:Pigments, Biological; D011492:Protein Hydrolysates; D011758:Pyrroles; D002701:Chloramphenicol; D011353:Prodigiosin; D010100:Oxygen