TY  - CHAP
M1  - Book, Section
TI  - Errors of Lysine Metabolism
A1  - Cox, Rody P.
A2  - Valle, David L.
A2  - Antonarakis, Stylianos
A2  - Ballabio, Andrea
A2  - Beaudet, Arthur L.
A2  - Mitchell, Grant A.
PY  - 2019
T2  - The Online Metabolic and Molecular Bases of Inherited Disease
AB  - Familial  hyperlysinemia  is  an  autosomal  recessive  disease  caused  by  a  defect  in  the  bifunctional  protein  α-aminoadipic  semialdehyde  synthase.  The  two  associated  enzyme  activities,  lysine-ketoglutarate  reductase  and  saccharopine  dehydrogenase,  normally  initiate  the  degradation  of  lysine  by  removal  of  the  ε  amino  group.  In  familial  hyperlysinemia,  both  activities  are  reduced  to  10  percent  of  normal  or  less,  causing  hyperlysinemia  and  lysinuria,  frequently  accompanied  by  a  relatively  mild  saccharopinuria.  The  condition  appears  to  be  benign.  A  variant,  saccharopinuria,  has  been  described  in  which  30  percent  of  lysine-ketoglutarate  activity  was  retained  and  the  saccharopine  dehydrogenase  activity  was  undetectable.  Saccharopinuria  was  prominent,  exceeding  the  associated  lysinuria.  Experience  with  the  variant  is  too  limited  to  know  if  this  metabolic  abnormality  causes  disease.Removal  of  the  α  amino  group  of  lysine  constitutes  a  minor  pathway  for  lysine  degradation  in  most  tissues,  with  pipecolic  acid  as  a  product.  Hyperpipecolatemia  is  regularly  observed  in  familial  hyperlysinemia  as  an  overflow  phenomenon.  It  is  also  a  common  concomitant  of  Zellweger  syndrome,  as  the  result  of  a  defect  in  peroxisome  formation  and  the  consequent  deficiency  of  L-pipecolic  acid  oxidase  activity.  A  convincing  example  of  a  patient  with  hyperpipecolatemia  as  a  primary  defect  has  not  been  reported.  The  hyperpipecolatemia  in  Zellweger  syndrome  becomes  manifest  after  the  major  symptoms  are  already  evident,  suggesting  that  it  is  not  a  significant  contributing  factor.  
SN  - 
PB  - McGraw-Hill Education
CY  - New York, NY
Y2  - 2024/04/18
UR  - ommbid.mhmedical.com/content.aspx?aid=1181435567
ER  -