scholarly journals TyrR, the regulator of aromatic amino acid metabolism, is required for mice infection of Yersinia pestis

2015 ◽  
Vol 6 ◽  
Author(s):  
Zhongliang Deng ◽  
Zizhong Liu ◽  
Junming He ◽  
Jing Wang ◽  
Yanfeng Yan ◽  
...  
Keyword(s):  
Amino Acid ◽  
Yersinia Pestis ◽  
Aromatic Amino Acid ◽  
Amino Acid Metabolism ◽  
Acid Metabolism ◽  
Aromatic Amino Acid Metabolism

scholarly journals Putative Horizontally Acquired Genes, Highly Transcribed during Yersinia pestis Flea Infection, Are Induced by Hyperosmotic Stress and Function in Aromatic Amino Acid Metabolism

2020 ◽  
Vol 202 (11) ◽  
Author(s):  
Luary C. Martínez-Chavarría ◽  
Janelle Sagawa ◽  
Jessica Irons ◽  
Angela K. Hinz ◽  
Athena Lemon ◽  
...  
Keyword(s):  
Gene Expression ◽  
Amino Acid ◽  
Yersinia Pestis ◽  
Salinity Stress ◽  
Aromatic Amino Acid ◽  
Amino Acid Metabolism ◽  
Acid Metabolism ◽  
Gc Content ◽  
Content Type ◽  
Aromatic Amino Acid Metabolism

ABSTRACT While alternating between insects and mammals during its life cycle, Yersinia pestis, the flea-transmitted bacterium that causes plague, regulates its gene expression appropriately to adapt to these two physiologically disparate host environments. In fleas competent to transmit Y. pestis, low-GC-content genes y3555, y3551, and y3550 are highly transcribed, suggesting that these genes have a highly prioritized role in flea infection. Here, we demonstrate that y3555, y3551, and y3550 are transcribed as part of a single polycistronic mRNA comprising the y3555, y3554, y3553, y355x, y3551, and y3550 genes. Additionally, y355x-y3551-y3550 compose another operon, while y3550 can be also transcribed as a monocistronic mRNA. The expression of these genes is induced by hyperosmotic salinity stress, which serves as an explicit environmental stimulus that initiates transcriptional activity from the predicted y3550 promoter. Y3555 has homology to pyridoxal 5′-phosphate (PLP)-dependent aromatic aminotransferases, while Y3550 and Y3551 are homologous to the Rid protein superfamily (YjgF/YER057c/UK114) members that forestall damage caused by reactive intermediates formed during PLP-dependent enzymatic activity. We demonstrate that y3551 specifically encodes an archetypal RidA protein with 2-aminoacrylate deaminase activity but Y3550 lacks Rid deaminase function. Heterologous expression of y3555 generates a critical aspartate requirement in a Salmonella enterica aspC mutant, while its in vitro expression, and specifically its heterologous coexpression with y3550, enhances the growth rate of an Escherichia coli ΔaspC ΔtyrB mutant in a defined minimal amino acid-supplemented medium. Our data suggest that the y3555, y3551, and y3550 genes operate cooperatively to optimize aromatic amino acid metabolism and are induced under conditions of hyperosmotic salinity stress. IMPORTANCE Distinct gene repertoires are expressed during Y. pestis infection of its flea and mammalian hosts. The functions of many of these genes remain predicted or unknown, necessitating their characterization, as this may provide a better understanding of Y. pestis specialized biological adaptations to the discrete environments of its two hosts. This study provides functional context to adjacently clustered horizontally acquired genes predominantly expressed in the flea host by deciphering their fundamental processes with regard to (i) transcriptional organization, (ii) transcription activation signals, and (iii) biochemical function. Our data support a role for these genes in osmoadaptation and aromatic amino acid metabolism, highlighting these as preferential processes by which Y. pestis gene expression is modulated during flea infection.

Aromatic amino acid metabolism of neonatal piglets receiving TPN: effect of tyrosine precursors

1994 ◽  
Vol 267 (5) ◽  
pp. E672-E679 ◽  
Author(s):  
L. J. Wykes ◽  
J. D. House ◽  
R. O. Ball ◽  
P. B. Pencharz
Keyword(s):  
Amino Acid ◽  
Aromatic Amino Acid ◽  
Amino Acid Metabolism ◽  
Acid Metabolism ◽  
Central Line ◽  
High Plasma ◽  
Control Group ◽  
Neonatal Piglets ◽  
Aromatic Amino Acid Metabolism ◽  
Plasma Tyrosine

Low tyrosine solubility in total parenteral nutrition (TPN) solutions complicates meeting the aromatic amino acid needs of infants. This study compared the effectiveness of two tyrosine precursors to supply the aromatic amino acid needs of TPN-fed neonatal piglets with a control group in which total aromatic acid needs were met by the addition of phenylalanine (Phe). Eighteen 3-day-old male Yorkshire piglets (6/group) received TPN for 8 days by central line. The solution was supplemented with Phe or one of the following two tyrosine precursors: N-acetyltyrosine (N-AcTyr) or glycyltyrosine (GlyTyr). Aromatic amino acid metabolism, growth, and nitrogen utilization were measured. Average amino acid and energy intakes were 14.6 g.kg-1.day-1 and 1,050 kJ.kg-1.day-1. Nitrogen balance and utilization were significantly higher (P < 0.05) in piglets in the control Phe group and on the GlyTyr regimen. The high urinary excretion of N-AcTyr (65%) confirms its low bioavailability. Flux and oxidation were significantly higher (P < 0.05) in the Phe group. High plasma Phe levels and excretion of Phe catabolites, as well as the high plasma tyrosine in the GlyTyr group, indicate that current strategies employed to meet the aromatic amino acid needs of neonates on TPN need further refinement.

scholarly journals Aromatic Amino Acid Metabolism during Liver Failure

2007 ◽  
Vol 137 (6) ◽  
pp. 1579S-1585S ◽  
Author(s):  
Cornelis H. C. Dejong ◽  
Marcel C. G. van de Poll ◽  
Peter B. Soeters ◽  
Rajiv Jalan ◽  
Steven W. M. Olde Damink
Keyword(s):  
Amino Acid ◽  
Liver Failure ◽  
Aromatic Amino Acid ◽  
Amino Acid Metabolism ◽  
Acid Metabolism ◽  
Aromatic Amino Acid Metabolism

Regulation of hepatic aromatic amino acid metabolism

1986 ◽  
Vol 14 (6) ◽  
pp. 999-1001 ◽  
Author(s):  
CHRISTOPHER I. POGSON ◽  
MARK SALTER ◽  
RICHARD G. KNOWLES
Keyword(s):  
Amino Acid ◽  
Aromatic Amino Acid ◽  
Amino Acid Metabolism ◽  
Acid Metabolism ◽  
Aromatic Amino Acid Metabolism
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