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1554  structures 7884  species 0  interactions 42571  sequences 542  architectures

Clan: Calycin (CL0116)


Calycin superfamily Add an annotation

The calycin structural superfamily [1-3] includes the lipocalins, the fatty acid-binding proteins (FABPs).

This clan contains 44 families and the total number of domains in the clan is 42571. The clan was built by A Bateman.

Literature references

  1. Flower DR, North AC, Sansom CE; , Biochim Biophys Acta 2000;1482:9-24.: The lipocalin protein family: structural and sequence overview. PUBMED:11058743 EPMC:11058743
  2. Flower DR; , FEBS Lett 1993;333:99-102.: Structural relationship of streptavidin to the calycin protein superfamily. PUBMED:8224179 EPMC:8224179
  3. Flower DR, North AC, Attwood TK; , Protein Sci 1993;2:753-761.: Structure and sequence relationships in the lipocalins and related proteins. PUBMED:7684291 EPMC:7684291


This clan contains the following 44 member families:

ApoM Calycin_like CpeS CpeT CrtC DUF1579 DUF1934 DUF2147 DUF3255 DUF3598 DUF3642 DUF3833 DUF4166 DUF4488 DUF4822 DUF4847 DUF4923 DUF5004 DUF5640 GH43_C His_binding Lipocalin Lipocalin_2 Lipocalin_3 Lipocalin_4 Lipocalin_5 Lipocalin_7 Lipocalin_8 Lipocalin_9 Luciferase_cat META MoaF MoaF_C MxiM Nitrophorin NlpE PA_decarbox Pallilysin Svf1 Svf1_C THAP4_heme-bd Triabin VDE ZinT

External database links

Domain organisation

Below is a listing of the unique domain organisations or architectures from this clan. More...

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The table below shows the number of occurrences of each domain throughout the sequence database. More...

Pfam family Num. domains Alignment
Lipocalin (PF00061) 9209 (21.6%) View
META (PF03724) 4572 (10.7%) View
Lipocalin_2 (PF08212) 3817 (9.0%) View
DUF2147 (PF09917) 3060 (7.2%) View
THAP4_heme-bd (PF08768) 2939 (6.9%) View
DUF1934 (PF09148) 1514 (3.6%) View
CrtC (PF07143) 1375 (3.2%) View
Lipocalin_9 (PF17186) 1345 (3.2%) View
Lipocalin_4 (PF13648) 1194 (2.8%) View
Lipocalin_7 (PF14651) 1115 (2.6%) View
DUF3833 (PF12915) 1033 (2.4%) View
Lipocalin_5 (PF13924) 989 (2.3%) View
NlpE (PF04170) 961 (2.3%) View
DUF4166 (PF13761) 908 (2.1%) View
Svf1_C (PF17187) 840 (2.0%) View
CpeT (PF06206) 829 (1.9%) View
Svf1 (PF08622) 820 (1.9%) View
DUF1579 (PF07617) 684 (1.6%) View
GH43_C (PF16369) 578 (1.4%) View
CpeS (PF09367) 573 (1.3%) View
VDE (PF07137) 553 (1.3%) View
PA_decarbox (PF05870) 527 (1.2%) View
ZinT (PF09223) 490 (1.2%) View
Pfam family Num. domains Alignment
DUF3598 (PF12204) 446 (1.0%) View
ApoM (PF11032) 371 (0.9%) View
MoaF (PF10703) 273 (0.6%) View
MoaF_C (PF17409) 247 (0.6%) View
Calycin_like (PF13944) 188 (0.4%) View
DUF5004 (PF16395) 166 (0.4%) View
DUF4822 (PF16103) 154 (0.4%) View
DUF4923 (PF16270) 149 (0.4%) View
Lipocalin_3 (PF12702) 148 (0.3%) View
Lipocalin_8 (PF16585) 134 (0.3%) View
DUF4488 (PF14869) 78 (0.2%) View
Triabin (PF03973) 74 (0.2%) View
DUF5640 (PF18692) 60 (0.1%) View
DUF4847 (PF16139) 39 (0.1%) View
Nitrophorin (PF02087) 33 (0.1%) View
Pallilysin (PF18663) 31 (0.1%) View
His_binding (PF02098) 31 (0.1%) View
DUF3642 (PF12182) 21 (0.0%) View
MxiM (PF11441) 2 (0.0%) View
DUF3255 (PF11631) 1 (0.0%) View
Luciferase_cat (PF10285) 0 (0.0%) View
Total: 44 Total: 42571
No alignment ℹ

Please note: Clan alignments can be very large and can cause problems for some browsers. Read the note above before viewing.

Family relationships

This diagram shows the relationships between members of this clan. More...

Species distribution

Tree controls


This tree shows the occurrence of the domains in this clan across different species. More...



For those sequences which have a structure in the Protein DataBank, we use the mapping between UniProt, PDB and Pfam coordinate systems from the MSD group, to allow us to map Pfam domains onto UniProt three-dimensional structures. The table below shows the mapping between the Pfam families in this clan, the corresponding UniProt entries, and the region of the three-dimensional structures that are available for that sequence.

Loading structure mapping...