Home  |  Contact
Due to scheduled maintenance work, this service will not be available from Tuesday August 23rd 06:00 pm until Wednesday August 24th 08:00 am CEST. Apologies for the inconvenience.

UniProtKB/Swiss-Prot Q13510: Variant p.Arg333Cys

Acid ceramidase
Gene: ASAH1
Variant information

Variant position:  333
The position of the amino-acid change on the UniProtKB canonical protein sequence.

Type of variant:  US
The variants are classified into three categories: LP/P, LB/B and US.
  • LP/P: likely pathogenic or pathogenic.
  • LB/B: likely benign or benign.
  • US: uncertain significance

Residue change:  From Arginine (R) to Cysteine (C) at position 333 (R333C, p.Arg333Cys).
Indicates the amino acid change of the variant. The one-letter and three-letter codes for amino acids used in UniProtKB/Swiss-Prot are those adopted by the commission on Biochemical Nomenclature of the IUPAC-IUB.

Physico-chemical properties:  Change from large size and basic (R) to medium size and polar (C)
The physico-chemical property of the reference and variant residues and the change implicated.

BLOSUM score:  -3
The score within a Blosum matrix for the corresponding wild-type to variant amino acid change. The log-odds score measures the logarithm for the ratio of the likelihood of two amino acids appearing by chance. The Blosum62 substitution matrix is used. This substitution matrix contains scores for all possible exchanges of one amino acid with another:
  • Lowest score: -4 (low probability of substitution).
  • Highest score: 11 (high probability of substitution).
More information can be found on the following page

Variant description:  In FRBRL; unknown pathological significance.
Any additional useful information about the variant.

Other resources:  
Links to websites of interest for the variant.

Sequence information

Variant position:  333
The position of the amino-acid change on the UniProtKB canonical protein sequence.

Protein sequence length:  395
The length of the canonical sequence.

The residue change on the sequence. Unless the variant is located at the beginning or at the end of the protein sequence, both residues upstream (20) and downstream (20) of the variant will be shown.

Residue conservation: 
The multiple alignment of the region surrounding the variant against various orthologous sequences.







Sequence annotation in neighborhood:  
The regions or sites of interest surrounding the variant. In general the features listed are posttranslational modifications, binding sites, enzyme active sites, local secondary structure or other characteristics reported in the cited references. The "Sequence annotation in neighborhood" lines have a fixed format:
  • Type: the type of sequence feature.
  • Positions: endpoints of the sequence feature.
  • Description: contains additional information about the feature.

Chain 143 – 395 Acid ceramidase subunit beta
Site 320 – 320 Important for catalytic activity
Site 333 – 333 Important for catalytic activity
Glycosylation 342 – 342 N-linked (GlcNAc...) asparagine
Glycosylation 348 – 348 N-linked (GlcNAc...) asparagine
Disulfide bond 31 – 340 Interchain (between alpha and beta subunits)
Mutagenesis 320 – 320 N -> A. Strongly decreased autocatalytic processing. Mildly decreased ceramidase activity.
Mutagenesis 333 – 333 R -> Q. Mildly decreased autocatalytic processing. Loss of ceramidase activity.
Mutagenesis 342 – 342 N -> Q. Loss of ceramide catabolic process.
Mutagenesis 348 – 348 N -> Q. No effect on ceramide catabolic process.

Literature citations

Atypical presentation of infantile-onset farber disease with novel ASAH1 mutations.
Kim S.Y.; Choi S.A.; Lee S.; Lee J.S.; Hong C.R.; Lim B.C.; Kang H.J.; Kim K.J.; Park S.H.; Choi M.; Chae J.H.;
Am. J. Med. Genet. A 170:3023-3027(2016)
Cited for: VARIANTS FRBRL ARG-235 AND CYS-333;

Disclaimer: Any medical or genetic information present in this entry is provided for research, educational and informational purposes only. They are not in any way intended to be used as a substitute for professional medical advice, diagnostic, treatment or care.