Chlorhämin (Ferriporphyrinchlorid) als Bakterienwuchsstoff I

Jensen, J.; Thofern, E

doi:10.1515/znb-1953-1009

Cited by 44 publications

(13 citation statements)

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“…Later work showed that the mutant grew without haemin in a medium containing acetate or pyruvate ; purines and uracil increased growth under these conditions (Lascelles, 1956). The mutant did not form haem compounds when grown on acetate in place of haemin since organisms grown in this way neither respired nor reduced nitrate; these activities were present only in organisms grown on haemin (Jensen & Thofern, 1953; Lascelles, 1956). In the present work the requirement of the mutant and parent strains for acetate has been examined more thoroughly.…”

Section: Introductionmentioning

confidence: 89%

The Requirement for Acetate of a Streptomycin-resistant Strain of Staphylococcus aureus

Gardner

Lascelles

1962

Journal of General Microbiology

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SUMMARYA streptomycin-resistant strain of Staphylococcus aureus, which requires haemin for aerobic growth, grew either aerobically or anaerobically in the absence of haemin provided the medium was supplemented with acetate or pyruvate; growth with these organic acids was increased by uracil and purines. The parent drug-sensitive strain grew aerobically without haemin but when grown anaerobically required either uracil or acetate or pyruvate. With both strains mevalonate replaced acetate and was about ten times more active.The products of glucose fermentation by both strains showed no gross difference, lactate being predominant (about 85 yo of the glucose carbon) ;only small amounts of acetate were detected. Under aerobic conditions suspensions of the parent strain oxidized glucose to acetate which accumulated. The mutant strain oxidized glucose to acetate only when previously grown with haemin or when haemin was added to the suspension of organisms. When the organism was grown with acetate in place of haemin, lactate was the predominant product. The ability of the mutant to form sufficient acetate from glucose for biosynthetic purposes is apparently dependent on a functional electron transport chain involving haemoproteins. A nicotinamide-adenine dinucleotide-linked lactate dehydrogenase and a pyruvate oxidizing system are present in extracts of both organisms. The activity of these enzymes in the mutant strain was similar whether the organisms were grown on haemin or acetate,

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Section: Introductionmentioning

confidence: 89%

The Requirement for Acetate of a Streptomycin-resistant Strain of Staphylococcus aureus

Gardner

Lascelles

1962

Journal of General Microbiology

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“…The wild type strain of Staphylococcus aureus ( A 51 1) and the hememutant derived from it were originally described by Jensen and Thofern. 3 The heme-mutant of Escherichia coli was strain H7, isolated by Beljanski and Beljanski;4 wild type strain W was also used. Stock cultures were maintained as described 5 The basal medium2 contained amino acids and vitamins, with addition of 10 or 50 mM glucose after autoclaving.…”

Section: Methodsmentioning

confidence: 99%

Anaerobic Growth Requirements of Staphylococci and the Enzymes of Pyrimidine Synthesis

Lascelles

1974

Annals of the New York Academy of Sciences

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“…For example, dwarf colonies of Salmonella ( Eberthella typhosa ) were isolated as early as in 1910, and several studies describe isolation of small colonies from aging bacterial cultures and cultures treated with, e.g. lithium chloride (reviewed in Swingle, 1935) or streptomycin (Jensen and Thofern, 1953; Beljanski, 1957).…”

Section: Introductionmentioning

confidence: 99%

Escape from growth restriction in small colony variants of Salmonella typhimurium by gene amplification and mutation

Pränting

Andersson²

2010

Molecular Microbiology

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SummaryAntibiotic resistance in bacteria is generally associated with fitness costs that often can be reduced by second-site compensatory mutations. Here, we examined how a protamine-resistant small colony variant of Salmonella typhimurium adapts to the growth reduction conferred by a resistance mutation in hemC (encoding a haem-biosynthesis enzyme). We show that adaptation occurs in a multi-step process where fitness is successively increased. Thus, the initial adaptive response was selection for an unstable gene amplification of the mutant hemC gene that provided a small fitness increase. Fitness was increased further by a mutation that restored HemC function in one gene copy, relaxing selection for the amplification. Subsequently, the amplification segregated back to the haploid state and even higher fitness. The end result was in most cases mutant strains with a hemC sequence different from that of the wild-type strain. These findings suggest that gene amplification facilitates adaptive evolution. A higher gene dosage increases the target size for compensatory mutations and improves fitness of the cell, thereby allowing an increase in the population size, further increasing the probability of a subsequent stable mutation. Our results provide a novel genetic basis for growth compensation in small colony variants.

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Chlorhämin (Ferriporphyrinchlorid) als Bakterienwuchsstoff I

Cited by 44 publications

References 0 publications

The Requirement for Acetate of a Streptomycin-resistant Strain of Staphylococcus aureus

The Requirement for Acetate of a Streptomycin-resistant Strain of Staphylococcus aureus

Anaerobic Growth Requirements of Staphylococci and the Enzymes of Pyrimidine Synthesis

Escape from growth restriction in small colony variants of Salmonella typhimurium by gene amplification and mutation

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