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Item _chem_comp.one_letter_code

Description

              For standard polymer components, the one-letter code for
               the component. If there is not a standard one-letter code
               for this component, or if this is a non-polymer
               component, the one-letter code should be given as 'X'.
               This code may be preceded by a '+' character to indicate
               that the component is a modification of a standard
               component.

Category

Item Examples

Example 1:

alanine or adenine

A

Example 2:

ambiguous asparagine/aspartic acid

B

Example 3:

arginine

R

Example 4:

asparagine

N

Example 5:

aspartic acid

D

Example 6:

cysteine or cystine or cytosine

C

Example 7:

glutamine

Q

Example 8:

glutamic acid

E

Example 9:

ambiguous glutamine/glutamic acid

Z

Example 10:

glycine or guanine

G

Example 11:

histidine

H

Example 12:

isoleucine

I

Example 13:

leucine

L

Example 14:

lysine

K

Example 15:

methionine

M

Example 16:

phenylalanine

F

Example 17:

proline

P

Example 18:

serine

S

Example 19:

threonine or thymine

T

Example 20:

tryptophan

W

Example 21:

tyrosine

Y

Example 22:

valine

V

Example 23:

uracil

U

Example 24:

water

O

Example 25:

other

X

Mandatory Code

Data Type Code

 

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