Literature summary for 2.7.13.3 extracted from

Shimura, Y.; Shiraiwa, Y.; Suzuki, I.
Characterization of the subdomains in the N-terminal region of histidine kinase Hik33 in the cyanobacterium Synechocystis sp. PCC 6803 (2012), Plant Cell Physiol., 53, 1255-1266.

Cloned(Commentary)

Cloned (Comment)	Organism
gene hik33, the chimeric gene for Hik33n-SphSc, integrated into the chromosomes, is expressed in Synechocystis from the original promoter of the sphS gene, and the copy number of each chimeric gene is exactly one per chromosome, subcloning in Escherichia coli strain JM109. Quantitative expression analysis of unaltered Hik33n-SphSc chimera and mutants under non-stressed conditions and salt-stressed conditions, overview	Synechocystis sp.
gene sphS, the chimeric gene for Hik33n-SphSc, integrated into the chromosomes, is expressed in Synechocystis from the original promoter of the sphS gene, and the copy number of each chimeric gene is exactly one per chromosome, subcloning in Escherichia coli strain JM109. Quantitative expression analysis of unaltered Hik33n-SphSc chimera and mutants under non-stressed conditions and salt-stressed conditions, overview	Synechocystis sp.

Cloned (Comment)

Organism

gene hik33, the chimeric gene for Hik33n-SphSc, integrated into the chromosomes, is expressed in Synechocystis from the original promoter of the sphS gene, and the copy number of each chimeric gene is exactly one per chromosome, subcloning in Escherichia coli strain JM109. Quantitative expression analysis of unaltered Hik33n-SphSc chimera and mutants under non-stressed conditions and salt-stressed conditions, overview

Synechocystis sp.

gene sphS, the chimeric gene for Hik33n-SphSc, integrated into the chromosomes, is expressed in Synechocystis from the original promoter of the sphS gene, and the copy number of each chimeric gene is exactly one per chromosome, subcloning in Escherichia coli strain JM109. Quantitative expression analysis of unaltered Hik33n-SphSc chimera and mutants under non-stressed conditions and salt-stressed conditions, overview

Synechocystis sp.

Protein Variants

Protein Variants	Comment	Organism
D300A	site-directed mutagenesis, the mutation might change the dimeric configuration of the PAS domain, thereby enhancing the negative effect on kinase activity. The D300A-mutated PAS domain of Hik33 also forms dimer in the assay. The Hik33n-SphSc mutant shows reduced expression under non-stressed and salt-stressed conditions compared to unaltered Hik33n-SphSc	Synechocystis sp.
D389A	site-directed mutagenesis, the Hik33n-SphSc mutant shows only slightly reduced expression under non-stressed conditions and highly reduced expression under salt-stressed conditions compared to unaltered Hik33n-SphSc	Synechocystis sp.
D412N	site-directed mutagenesis, the Hik33n-SphSc mutant shows only slightly reduced expression under non-stressed conditions and highly reduced expression under salt-stressed conditions compared to unaltered Hik33n-SphSc	Synechocystis sp.
E416Q	site-directed mutagenesis, the Hik33n-SphSc mutant shows normal expression under non-stressed conditions and highly reduced expression under salt-stressed conditions compared to unaltered Hik33n-SphSc	Synechocystis sp.
G405A	site-directed mutagenesis, the Hik33n-SphSc mutant shows only slightly reduced expression under non-stressed conditions and highly reduced expression under salt-stressed conditions compared to unaltered Hik33n-SphSc	Synechocystis sp.
G405S	site-directed mutagenesis, the Hik33n-SphSc mutant shows only slightly reduced expression under non-stressed conditions and no expression under salt-stressed conditions compared to unaltered Hik33n-SphSc	Synechocystis sp.
additional information	generation of a series of chimeric proteins that include the N-terminal region of Hik33 (M1-A422) and the C-terminal region (Q197-P430) of SphS, a histidine kinase that senses phosphate-deficient conditions. The chimeric protein Hik33n-SphSc regulates expression of the phoA gene under stress conditions. Under standard growth conditions, cells that harbor the gene for Hik33n-SphSc express phoA, whereas the expression of phoA is repressed under salt stress and under cold stress	Synechocystis sp.
additional information	generation of a series of chimeric proteins that include the N-terminal region of stress regulator histidine kinase Hik33 (M1-A422) and the C-terminal region (Q197-P430) of SphS. The chimeric protein Hik33n-SphSc regulates expression of the phoA gene under stress conditions. Under standard growth conditions, cells that harbor the gene for Hik33n-SphSc express phoA, whereas the expression of phoA is repressed under salt stress and under cold stress	Synechocystis sp.
N309A	site-directed mutagenesis, the Hik33n-SphSc mutant shows only slightly reduced expression under non-stressed conditions and highly reduced expression under salt-stressed conditions compared to unaltered Hik33n-SphSc	Synechocystis sp.
Q411E	site-directed mutagenesis, the Hik33n-SphSc mutant shows normal expression under non-stressed conditions and highly reduced expression under salt-stressed conditions compared to unaltered Hik33n-SphSc	Synechocystis sp.
R377A	site-directed mutagenesis, the Hik33n-SphSc mutant shows only slightly reduced expression under non-stressed conditions and highly reduced expression under salt-stressed conditions compared to unaltered Hik33n-SphSc	Synechocystis sp.
R400S/R404A	site-directed mutagenesis, the Hik33n-SphSc mutant shows normal expression under non-stressed conditions and highly reduced expression under salt-stressed conditions compared to unaltered Hik33n-SphSc	Synechocystis sp.
R404A	site-directed mutagenesis, the Hik33n-SphSc mutant shows normal expression under non-stressed conditions and highly reduced expression under salt-stressed conditions compared to unaltered Hik33n-SphSc	Synechocystis sp.
R415E	site-directed mutagenesis, the mutation might change the dimeric configuration of the PAS domain, thereby enhancing the negative effect on kinase activity. The Hik33n-SphSc mutant shows reduced expression under non-stressed and salt-stressed conditions compared to unaltered Hik33n-SphSc	Synechocystis sp.
T409V	site-directed mutagenesis, the Hik33n-SphSc mutant shows only slightly reduced expression under non-stressed conditions and no expression under salt-stressed conditions compared to unaltered Hik33n-SphSc	Synechocystis sp.
T414V	site-directed mutagenesis, the Hik33n-SphSc mutant shows only slightly reduced expression under non-stressed conditions and no expression under salt-stressed conditions compared to unaltered Hik33n-SphSc	Synechocystis sp.
V395A	site-directed mutagenesis, the Hik33n-SphSc mutant shows only slightly reduced expression under non-stressed conditions and highly reduced expression under salt-stressed conditions compared to unaltered Hik33n-SphSc	Synechocystis sp.
W318A	site-directed mutagenesis, the mutation might change the dimeric configuration of the PAS domain, thereby enhancing the negative effect on kinase activity. The W318A-mutated PAS domain of Hik33 also forms dimer in the assay. The Hik33n-SphSc mutant shows reduced expression under non-stressed and salt-stressed conditions compared to unaltered Hik33n-SphSc	Synechocystis sp.

Localization

Localization	Comment	Organism	GeneOntology No.	Textmining
membrane	transmembrane enzyme	Synechocystis sp.	16020	-

Metals/Ions

Metals/Ions	Comment	Organism	Structure
Mg2+	required	Synechocystis sp.

Natural Substrates/ Products (Substrates)

Natural Substrates	Organism	Comment (Nat. Sub.)	Natural Products	Comment (Nat. Pro.)	Rev.	Reac.
ATP + protein L-histidine	Synechocystis sp.	-	ADP + protein N-phospho-L-histidine	-	?

Organism

Organism	UniProt	Comment	Textmining
Synechocystis sp.	-	-	-
Synechocystis sp.	Q55586	-	-

Substrates and Products (Substrate)

Substrates	Comment Substrates	Organism	Products	Comment (Products)	Rev.	Reac.
ATP + protein L-histidine	-	Synechocystis sp.	ADP + protein N-phospho-L-histidine	-	?

Subunits

Subunits	Comment	Organism
More	analysis of the enzyme subdomains of the N-terminal region	Synechocystis sp.
More	Hik33 has several subdomains in its N-terminal region, two of which are transmembrane (TM) helices (TM1 and TM2), and it is located on plasma and/or thylakoid membranes. The N-terminal region also includes a periplasmic loop region between the TM helices, a HAMP domain, and a PAS domain. Analysis of the enzyme subdomains of the N-terminal region	Synechocystis sp.

Synonyms

Synonyms	Comment	Organism
Hik33	-	Synechocystis sp.
SphS	-	Synechocystis sp.

Cofactor

Cofactor	Comment	Organism	Structure
ATP	-	Synechocystis sp.

General Information

General Information	Comment	Organism
malfunction	removal of the HAMP or the PAS domain from Hik33n-SphSc and substitutions of amino acid residues in the PAS domain influence kinase activity, overview. Subdomain-deleted variants of Hik33n-SphSc show reduced activity compared to the unaltered chimera	Synechocystis sp.
physiological function	histidine kinase Hik33 is one of the key regulators helping Synechocystis acclimate to multiple stress conditions, Hik33 may play important roles in allowing cells to acclimate to changing environmental conditions	Synechocystis sp.
physiological function	histidine kinase SphS senses phosphate-deficient conditions. SphS phosphorylates its cognate response regulator, SphR, under phosphate-deficient conditions and regulates the expression of the so-called pho regulon, which includes genes for acclimation to phosphate-deficient conditions, namely genes for a periplasmic alkaline phosphatase PhoA and phosphate transporters	Synechocystis sp.