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  1. Article ; Online: Deficiency in L-serine deaminase interferes with one-carbon metabolism and cell wall synthesis in Escherichia coli K-12.

    Zhang, Xiao / El-Hajj, Ziad W / Newman, Elaine

    Journal of bacteriology

    2010  Volume 192, Issue 20, Page(s) 5515–5525

    Abstract: Escherichia coli K-12 provided with glucose and a mixture of amino acids depletes L-serine more ... serine deaminases (SdaA, SdaB, and TdcG) of E. coli K-12 is unable to do this. The high level of L-serine ... quickly than any other amino acid even in the presence of ammonium sulfate. A mutant without three 4Fe4S L ...

    Abstract Escherichia coli K-12 provided with glucose and a mixture of amino acids depletes L-serine more quickly than any other amino acid even in the presence of ammonium sulfate. A mutant without three 4Fe4S L-serine deaminases (SdaA, SdaB, and TdcG) of E. coli K-12 is unable to do this. The high level of L-serine that accumulates when such a mutant is exposed to amino acid mixtures starves the cells for C(1) units and interferes with cell wall synthesis. We suggest that at high concentrations, L-serine decreases synthesis of UDP-N-acetylmuramate-L-alanine by the murC-encoded ligase, weakening the cell wall and producing misshapen cells and lysis. The inhibition by high L-serine is overcome in several ways: by a large concentration of L-alanine, by overproducing MurC together with a low concentration of L-alanine, and by overproducing FtsW, thus promoting septal assembly and also by overexpression of the glycine cleavage operon. S-Adenosylmethionine reduces lysis and allows an extensive increase in biomass without improving cell division. This suggests that E. coli has a metabolic trigger for cell division. Without that reaction, if no other inhibition occurs, other metabolic functions can continue and cells can elongate and replicate their DNA, reaching at least 180 times their usual length, but cannot divide.
    MeSH term(s) Alanine/metabolism ; Amino Acids/chemistry ; Amino Acids/metabolism ; Carbon/metabolism ; Cell Wall/metabolism ; Culture Media/chemistry ; Escherichia coli K12/genetics ; Escherichia coli K12/metabolism ; Escherichia coli Proteins/genetics ; Escherichia coli Proteins/metabolism ; Gene Expression Regulation, Bacterial/physiology ; Glucose/chemistry ; Glucose/metabolism ; Hypoxanthine/metabolism ; L-Serine Dehydratase/deficiency ; Mutation ; Promoter Regions, Genetic ; Serine/metabolism
    Chemical Substances Amino Acids ; Culture Media ; Escherichia coli Proteins ; casamino acids ; Hypoxanthine (2TN51YD919) ; Serine (452VLY9402) ; Carbon (7440-44-0) ; L-Serine Dehydratase (EC 4.3.1.17) ; Glucose (IY9XDZ35W2) ; Alanine (OF5P57N2ZX)
    Language English
    Publishing date 2010-08-20
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2968-3
    ISSN 1098-5530 ; 0021-9193
    ISSN (online) 1098-5530
    ISSN 0021-9193
    DOI 10.1128/JB.00748-10
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Deficiency in l-serine deaminase results in abnormal growth and cell division of Escherichia coli K-12.

    Zhang, Xiao / Newman, Elaine

    Molecular microbiology

    2008  Volume 69, Issue 4, Page(s) 870–881

    Abstract: ... in Escherichia coli K-12. A strain from which the three genes (sdaA, sdaB, tdcG) coding for this organism's three l ... The loss of the ability to deaminate l-serine severely impairs growth and cell division ... by methylation, that an unusually high intracellular l-serine concentration, in the presence of other amino acids ...

    Abstract The loss of the ability to deaminate l-serine severely impairs growth and cell division in Escherichia coli K-12. A strain from which the three genes (sdaA, sdaB, tdcG) coding for this organism's three l-serine deaminases had been deleted grows well in glucose minimal medium but, on subculture into minimal medium with glucose and casamino acids, it makes very large, abnormally shaped cells, many of which lyse. When inoculated into Luria-Bertani (LB) broth with or without glucose, it makes very long filaments. Provision of S-adenosylmethionine restores cell division in LB broth with glucose, and repairs much of the difficulty in growth in medium with casamino acids. We suggest that replication of E. coli is regulated by methylation, that an unusually high intracellular l-serine concentration, in the presence of other amino acids, starves the cell for S-adenosylmethionine and that it is the absence of S-adenosylmethionine and/or of C1-tetrahydrofolate derivatives that prevents normal cell division.
    MeSH term(s) Amino Acids/metabolism ; Amino Acids/pharmacology ; Cell Division/genetics ; Culture Media/metabolism ; Culture Media/pharmacology ; Escherichia coli/cytology ; Escherichia coli/drug effects ; Escherichia coli/enzymology ; Escherichia coli/growth & development ; Escherichia coli Proteins/genetics ; Escherichia coli Proteins/metabolism ; Gene Deletion ; L-Serine Dehydratase/genetics ; L-Serine Dehydratase/metabolism ; S-Adenosylmethionine/metabolism ; S-Adenosylmethionine/pharmacology
    Chemical Substances Amino Acids ; Culture Media ; Escherichia coli Proteins ; casamino acids ; S-Adenosylmethionine (7LP2MPO46S) ; L-Serine Dehydratase (EC 4.3.1.17)
    Language English
    Publishing date 2008-08
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 619315-8
    ISSN 1365-2958 ; 0950-382X
    ISSN (online) 1365-2958
    ISSN 0950-382X
    DOI 10.1111/j.1365-2958.2008.06315.x
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article: Deficiency in l-serine deaminase results in abnormal growth and cell division of Escherichia coli K-12

    Zhang, Xiao / Newman, Elaine

    Molecular microbiology. 2008 Aug., v. 69, no. 4

    2008  

    Abstract: ... in Escherichia coli K-12. A strain from which the three genes (sdaA, sdaB, tdcG) coding for this organism's three l ... The loss of the ability to deaminate l-serine severely impairs growth and cell division ... by methylation, that an unusually high intracellular l-serine concentration, in the presence of other amino acids ...

    Abstract The loss of the ability to deaminate l-serine severely impairs growth and cell division in Escherichia coli K-12. A strain from which the three genes (sdaA, sdaB, tdcG) coding for this organism's three l-serine deaminases had been deleted grows well in glucose minimal medium but, on subculture into minimal medium with glucose and casamino acids, it makes very large, abnormally shaped cells, many of which lyse. When inoculated into Luria-Bertani (LB) broth with or without glucose, it makes very long filaments. Provision of S-adenosylmethionine restores cell division in LB broth with glucose, and repairs much of the difficulty in growth in medium with casamino acids. We suggest that replication of E. coli is regulated by methylation, that an unusually high intracellular l-serine concentration, in the presence of other amino acids, starves the cell for S-adenosylmethionine and that it is the absence of S-adenosylmethionine and/or of C1-tetrahydrofolate derivatives that prevents normal cell division.
    Language English
    Dates of publication 2008-08
    Size p. 870-881.
    Publisher Blackwell Publishing Ltd
    Publishing place Oxford, UK
    Document type Article
    ZDB-ID 619315-8
    ISSN 1365-2958 ; 0950-382X
    ISSN (online) 1365-2958
    ISSN 0950-382X
    DOI 10.1111/j.1365-2958.2008.06315.x
    Database NAL-Catalogue (AGRICOLA)

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  4. Article: A novel L-serine deaminase activity in Escherichia coli K-12.

    Su, H / Newman, E B

    Journal of bacteriology

    1991  Volume 173, Issue 8, Page(s) 2473–2480

    Abstract: We demonstrate here that Escherichia coli K-12 synthesizes two different L-serine deaminases (L-SD ... catalyzing the nonoxidative deamination of L-serine to pyruvate, one coded for by the previously described ... sdaA gene and a second, hitherto undescribed enzyme which we call L-SD2. A strain carrying a null ...

    Abstract We demonstrate here that Escherichia coli K-12 synthesizes two different L-serine deaminases (L-SD) catalyzing the nonoxidative deamination of L-serine to pyruvate, one coded for by the previously described sdaA gene and a second, hitherto undescribed enzyme which we call L-SD2. A strain carrying a null mutation in sdaA made no detectable L-SD in minimal medium, but had activity in Luria broth. We describe a mutation, sdaX, which affects the regulation of L-SD2 and permits its expression in minimal medium, and an insertion mutation, sdaB, which abolishes L-SD2 activity completely. Both mutations lie near 60.5 min on the E. coli genetic map. The two L-SD enzymes have similar enzyme parameters, and both require posttranslational activation.
    MeSH term(s) Chromosome Mapping ; Cloning, Molecular ; Conjugation, Genetic ; Dithiothreitol/pharmacology ; Escherichia coli/metabolism ; Iron/pharmacology ; L-Serine Dehydratase/biosynthesis ; L-Serine Dehydratase/genetics ; Nucleic Acid Hybridization ; Plasmids ; Transduction, Genetic
    Chemical Substances Iron (E1UOL152H7) ; L-Serine Dehydratase (EC 4.3.1.17) ; Dithiothreitol (T8ID5YZU6Y)
    Language English
    Publishing date 1991-04
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2968-3
    ISSN 1098-5530 ; 0021-9193
    ISSN (online) 1098-5530
    ISSN 0021-9193
    DOI 10.1128/jb.173.8.2473-2480.1991
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article: An estimate of the extent of deamination of L-serine in auxotrophs of Escherichia coli K-12.

    Ramotar, D / Newman, E B

    Canadian journal of microbiology

    1986  Volume 32, Issue 11, Page(s) 842–846

    Abstract: We have shown that serine-glycine auxotrophs of Escherichia coli K-12 use exogenous L-serine ... inefficiently as a source of biosynthetic intermediates. Much of the L-serine supplied in the medium is not used ... to satisfy the auxotrophic requirement, owing to its diversion by L-serine deaminase, presumably to pyruvate ...

    Abstract We have shown that serine-glycine auxotrophs of Escherichia coli K-12 use exogenous L-serine inefficiently as a source of biosynthetic intermediates. Much of the L-serine supplied in the medium is not used to satisfy the auxotrophic requirement, owing to its diversion by L-serine deaminase, presumably to pyruvate. This is the first proof that the activity known as L-serine deaminase actually deaminates L-serine in vivo.
    MeSH term(s) Culture Media ; Escherichia coli/enzymology ; Escherichia coli/genetics ; Escherichia coli/growth & development ; Glycine/metabolism ; L-Serine Dehydratase/metabolism ; Mutation ; Serine/metabolism
    Chemical Substances Culture Media ; Serine (452VLY9402) ; L-Serine Dehydratase (EC 4.3.1.17) ; Glycine (TE7660XO1C)
    Language English
    Publishing date 1986-11
    Publishing country Canada
    Document type Comparative Study ; Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 280534-0
    ISSN 1480-3275 ; 0008-4166
    ISSN (online) 1480-3275
    ISSN 0008-4166
    DOI 10.1139/m86-155
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article: Use of gene fusions of the structural gene sdaA to purify L-serine deaminase 1 from Escherichia coli K-12.

    Su, H / Moniakis, J / Newman, E B

    European journal of biochemistry

    1993  Volume 211, Issue 3, Page(s) 521–527

    Abstract: ... gene fusions results in the copurification of L-serine deaminase 1. We conclude that sdaA is the structural ... gene for the latter enzyme. The purified L-serine deaminase 1 obtained after collagenase treatment ...

    Abstract The purification by affinity chromatography of beta-galactosidase from strains carrying sdaA/lacZ gene fusions results in the copurification of L-serine deaminase 1. We conclude that sdaA is the structural gene for the latter enzyme. The purified L-serine deaminase 1 obtained after collagenase treatment of an sdaA-collagen-lacZ fusion differs from the native enzyme by the addition of several amino acids at the C-terminal. Like the enzyme in crude extracts, this purified enzyme is catalytically inactive, and is activated by incubation with iron and dithiothreitol.
    MeSH term(s) Base Sequence ; Chromatography, High Pressure Liquid ; Cloning, Molecular ; Collagen/genetics ; Collagenases/metabolism ; Dithiothreitol/pharmacology ; Enzyme Activation/drug effects ; Escherichia coli/enzymology ; Escherichia coli/genetics ; Genes, Bacterial ; Iron/pharmacology ; L-Serine Dehydratase/genetics ; L-Serine Dehydratase/isolation & purification ; Molecular Sequence Data ; Mutagenesis, Site-Directed ; Plasmids ; Recombinant Fusion Proteins/isolation & purification ; Recombinant Fusion Proteins/metabolism ; beta-Galactosidase/genetics ; beta-Galactosidase/isolation & purification
    Chemical Substances Recombinant Fusion Proteins ; Collagen (9007-34-5) ; Iron (E1UOL152H7) ; beta-Galactosidase (EC 3.2.1.23) ; Collagenases (EC 3.4.24.-) ; L-Serine Dehydratase (EC 4.3.1.17) ; Dithiothreitol (T8ID5YZU6Y)
    Language English
    Publishing date 1993-02-01
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 3032-6
    ISSN 1432-1033 ; 0014-2956
    ISSN (online) 1432-1033
    ISSN 0014-2956
    DOI 10.1111/j.1432-1033.1993.tb17578.x
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article: The leucine regulon of Escherichia coli K-12: a mutation in rblA alters expression of L-leucine-dependent metabolic operons.

    Tuan, L R / D'Ari, R / Newman, E B

    Journal of bacteriology

    1990  Volume 172, Issue 8, Page(s) 4529–4535

    Abstract: ... by leucine. Selected for its ability to grow with L-serine as sole carbon source, the rbl-1::Tn10 mutant had ... high levels of L-serine deaminase activity (due to increased transcription of the structural gene) and ... of another amino acid-degrading enzyme, L-threonine dehydrogenase, and decreased transcription of the operons serA and ...

    Abstract We have isolated and characterized a highly pleiotropic Escherichia coli mutant affected in the activity of a number of enzymes involved in different metabolic pathways, all of which are regulated by leucine. Selected for its ability to grow with L-serine as sole carbon source, the rbl-1::Tn10 mutant had high levels of L-serine deaminase activity (due to increased transcription of the structural gene) and of another amino acid-degrading enzyme, L-threonine dehydrogenase, and decreased transcription of the operons serA and ilvIH, coding for biosynthetic enzymes. The rbl mutation suppressed the slow growth of a metK mutant, deficient in S-adenosylmethionine synthetase. Furthermore, metK mutants spontaneously accumulated faster-growing rbl-like derivatives, and a commonly used metK strain, RG62, carries such a mutation. The rbl gene is located near 20 min on the E. coli genetic map. All phenotypes of the rbl mutant could be observed in rbl+ strains cultivated in the presence of L-leucine, and exogenous L-leucine had little further effect on the rbl strains. We propose that the rbl gene product is the regulator of a global response to leucine.
    MeSH term(s) Alcohol Oxidoreductases/genetics ; Alcohol Oxidoreductases/metabolism ; DNA Transposable Elements ; Escherichia coli/genetics ; Genes, Regulator ; Genotype ; L-Serine Dehydratase/genetics ; L-Serine Dehydratase/metabolism ; Leucine/metabolism ; Methionine Adenosyltransferase/genetics ; Mutation ; Operon ; Transcription, Genetic ; beta-Galactosidase/genetics ; beta-Galactosidase/metabolism
    Chemical Substances DNA Transposable Elements ; Alcohol Oxidoreductases (EC 1.1.-) ; L-threonine 3-dehydrogenase (EC 1.1.1.103) ; Methionine Adenosyltransferase (EC 2.5.1.6) ; beta-Galactosidase (EC 3.2.1.23) ; L-Serine Dehydratase (EC 4.3.1.17) ; Leucine (GMW67QNF9C)
    Language English
    Publishing date 1990-08
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2968-3
    ISSN 1098-5530 ; 0021-9193
    ISSN (online) 1098-5530
    ISSN 0021-9193
    DOI 10.1128/jb.172.8.4529-4535.1990
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article: L-serine degradation in Escherichia coli K-12: a combination of L-serine, glycine, and leucine used as a source of carbon.

    Newman, E B / Walker, C

    Journal of bacteriology

    1982  Volume 151, Issue 2, Page(s) 777–782

    Abstract: Escherichia coli K-12 strain CU1008 cannot use L-serine as the sole carbon source, but it could use ... L-serine as an auxiliary carbon source with glucose, L-alanine, or pyruvate and could derive energy ... from L-serine to support oxygen uptake. CU1008 grew with L-serine if it was also provided with glycine ...

    Abstract Escherichia coli K-12 strain CU1008 cannot use L-serine as the sole carbon source, but it could use L-serine as an auxiliary carbon source with glucose, L-alanine, or pyruvate and could derive energy from L-serine to support oxygen uptake. CU1008 grew with L-serine if it was also provided with glycine and leucine. These may act by increasing the available activity of L-serine deaminase; other explanations are also explored.
    MeSH term(s) Energy Metabolism ; Escherichia coli/metabolism ; Glucose/metabolism ; Glycine/metabolism ; Leucine/metabolism ; Oxygen Consumption ; Serine/metabolism ; Triose-Phosphate Isomerase/metabolism
    Chemical Substances Serine (452VLY9402) ; Triose-Phosphate Isomerase (EC 5.3.1.1) ; Leucine (GMW67QNF9C) ; Glucose (IY9XDZ35W2) ; Glycine (TE7660XO1C)
    Language English
    Publishing date 1982-08
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2968-3
    ISSN 1098-5530 ; 0021-9193
    ISSN (online) 1098-5530
    ISSN 0021-9193
    DOI 10.1128/jb.151.2.777-782.1982
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article: L-serine degradation in Escherichia coli K-12: cloning and sequencing of the sdaA gene.

    Su, H S / Lang, B F / Newman, E B

    Journal of bacteriology

    1989  Volume 171, Issue 9, Page(s) 5095–5102

    Abstract: A new mutant of Escherichia coli K-12 unable to grow with L-serine, glycine, and L-leucine has been ... isolated by lambda plac Mu insertion and shown to be deficient in L-serine deaminase activity ... sequenced. The evidence is consistent with the hypothesis that sdaA is the structural gene for L-serine ...

    Abstract A new mutant of Escherichia coli K-12 unable to grow with L-serine, glycine, and L-leucine has been isolated by lambda plac Mu insertion and shown to be deficient in L-serine deaminase activity. The corresponding gene, sdaA, has been cloned from a prototrophic strain, and the clone has been characterized and sequenced. The evidence is consistent with the hypothesis that sdaA is the structural gene for L-serine deaminase. However, other possibilities are also considered. No significant homology with previously reported DNA or protein sequences was detected.
    MeSH term(s) Amino Acid Sequence ; Base Sequence ; Cloning, Molecular ; Coliphages/genetics ; Escherichia coli/enzymology ; Escherichia coli/genetics ; Genes ; Genes, Bacterial ; L-Serine Dehydratase/genetics ; Molecular Sequence Data ; Plasmids ; Restriction Mapping ; Serine/metabolism
    Chemical Substances Serine (452VLY9402) ; L-Serine Dehydratase (EC 4.3.1.17)
    Language English
    Publishing date 1989-09
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2968-3
    ISSN 1098-5530 ; 0021-9193
    ISSN (online) 1098-5530
    ISSN 0021-9193
    DOI 10.1128/jb.171.9.5095-5102.1989
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: A Systematic Review of Inflammatory Bowel Disease Epidemiology and Health Outcomes in Sexual and Gender Minority Individuals.

    Newman, Kira L / Chedid, Victor G / Boden, Elisa K

    Gastroenterology

    2023  Volume 164, Issue 6, Page(s) 866–871

    MeSH term(s) Humans ; Sexual and Gender Minorities ; Outcome Assessment, Health Care
    Language English
    Publishing date 2023-03-05
    Publishing country United States
    Document type Systematic Review ; Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 80112-4
    ISSN 1528-0012 ; 0016-5085
    ISSN (online) 1528-0012
    ISSN 0016-5085
    DOI 10.1053/j.gastro.2022.11.048
    Database MEDical Literature Analysis and Retrieval System OnLINE

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