ID RBS_LACSA Reviewed; 181 AA. AC Q40250; DT 15-DEC-1998, integrated into UniProtKB/Swiss-Prot. DT 01-NOV-1996, sequence version 1. DT 07-APR-2021, entry version 88. DE RecName: Full=Ribulose bisphosphate carboxylase small subunit, chloroplastic {ECO:0000255|HAMAP-Rule:MF_00860}; DE Short=RuBisCO small subunit {ECO:0000255|HAMAP-Rule:MF_00860}; DE Flags: Precursor; GN Name=RBCS {ECO:0000255|HAMAP-Rule:MF_00860}; OS Lactuca sativa (Garden lettuce). OC Eukaryota; Viridiplantae; Streptophyta; Embryophyta; Tracheophyta; OC Spermatophyta; Magnoliopsida; eudicotyledons; Gunneridae; Pentapetalae; OC asterids; campanulids; Asterales; Asteraceae; Cichorioideae; Cichorieae; OC Lactucinae; Lactuca. OX NCBI_TaxID=4236; RN [1] RP NUCLEOTIDE SEQUENCE [MRNA]. RA Hanyuu K.; RL Submitted (JAN-1993) to the EMBL/GenBank/DDBJ databases. CC -!- FUNCTION: RuBisCO catalyzes two reactions: the carboxylation of D- CC ribulose 1,5-bisphosphate, the primary event in carbon dioxide CC fixation, as well as the oxidative fragmentation of the pentose CC substrate. Both reactions occur simultaneously and in competition at CC the same active site. Although the small subunit is not catalytic it is CC essential for maximal activity. {ECO:0000255|HAMAP-Rule:MF_00860}. CC -!- SUBUNIT: Heterohexadecamer of 8 large and 8 small subunits. CC {ECO:0000255|HAMAP-Rule:MF_00860}. CC -!- SUBCELLULAR LOCATION: Plastid, chloroplast {ECO:0000255|HAMAP- CC Rule:MF_00860}. CC -!- MISCELLANEOUS: The basic functional RuBisCO is composed of a large CC chain homodimer in a 'head-to-tail' conformation. In form I RuBisCO CC this homodimer is arranged in a barrel-like tetramer with the small CC subunits forming a tetrameric 'cap' on each end of the 'barrel'. CC {ECO:0000255|HAMAP-Rule:MF_00860}. CC -!- SIMILARITY: Belongs to the RuBisCO small chain family. CC {ECO:0000255|HAMAP-Rule:MF_00860}. CC --------------------------------------------------------------------------- CC Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms CC Distributed under the Creative Commons Attribution (CC BY 4.0) License CC --------------------------------------------------------------------------- DR EMBL; D14001; BAA03103.1; -; mRNA. DR SMR; Q40250; -. DR PRIDE; Q40250; -. DR OrthoDB; 1258997at2759; -. DR GO; GO:0009507; C:chloroplast; IEA:UniProtKB-SubCell. DR GO; GO:0004497; F:monooxygenase activity; IEA:UniProtKB-KW. DR GO; GO:0016984; F:ribulose-bisphosphate carboxylase activity; IEA:UniProtKB-EC. DR GO; GO:0009853; P:photorespiration; IEA:UniProtKB-KW. DR GO; GO:0019253; P:reductive pentose-phosphate cycle; IEA:UniProtKB-KW. DR CDD; cd03527; RuBisCO_small; 1. DR Gene3D; 3.30.190.10; -; 1. DR HAMAP; MF_00859; RuBisCO_S_bact; 1. DR InterPro; IPR024681; RuBisCO_sc. DR InterPro; IPR000894; RuBisCO_sc_dom. DR InterPro; IPR024680; RuBisCO_ssu_N. DR InterPro; IPR036385; RuBisCO_ssu_sf. DR Pfam; PF12338; RbcS; 1. DR Pfam; PF00101; RuBisCO_small; 1. DR PRINTS; PR00152; RUBISCOSMALL. DR SMART; SM00961; RuBisCO_small; 1. DR SUPFAM; SSF55239; SSF55239; 1. PE 2: Evidence at transcript level; KW Calvin cycle; Carbon dioxide fixation; Chloroplast; Photorespiration; KW Photosynthesis; Plastid; Transit peptide. FT TRANSIT 1..56 FT /note="Chloroplast" FT /evidence="ECO:0000255|HAMAP-Rule:MF_00860" FT CHAIN 57..181 FT /note="Ribulose bisphosphate carboxylase small subunit, FT chloroplastic" FT /evidence="ECO:0000255|HAMAP-Rule:MF_00860" FT /id="PRO_0000031510" SQ SEQUENCE 181 AA; 20359 MW; CE6F3AD4E81F6075 CRC64; MASISSSAIA TVNRTTSTQA SLAAPFTGLK SNVAFPVTKK ANNDFSSLPS NGGRVQCMKV WPPIGLKKYE TLSYLPPLSD EALSKEIDYL IRNKWIPCLE FELEHGFVYR EHHHSPGYYD GRYWTMWKLP MFGCTDSAQV MKEVGECKKE YPNAFIRVIG FDNIRQVQCI SFIVAKPPGV L //