Activating Compound | Comment | Organism | Structure |
---|---|---|---|
additional information | exposure to light increases the autophosphorylation activity of the enzyme | Brucella abortus |
Cloned (Comment) | Organism |
---|---|
gene BAB2_0652, recombinant expression f the enzyme in a two-hybrid system with PdhS in frame with the lambdacl gene, coexpression with gene pdhS, recombinant expression of His-tagged lovhk and hk domains in Escherichia coli strain BL21(DE3) pLysS from pET24a plasmid, coexpression of phyR and lovR. Antibiotic resistance complementation assays with the enzyme in Escherichia coli, overview. Realtime quantitative RT-PCR expression analysis | Brucella abortus |
Protein Variants | Comment | Organism |
---|---|---|
additional information | construction of a LOVHK knockout mutant | Brucella abortus |
Metals/Ions | Comment | Organism | Structure |
---|---|---|---|
Mg2+ | required | Brucella abortus |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
ATP + protein L-histidine | Brucella abortus | - |
ADP + protein N-phospho-L-histidine | - |
? | |
ATP + protein L-histidine | Brucella abortus 2308 | - |
ADP + protein N-phospho-L-histidine | - |
? | |
additional information | Brucella abortus | LOVHK is able to phosphotransfer to the central regulator of the GSR system in Brucella, specific interaction with its cognate response regulators | ? | - |
? | |
additional information | Brucella abortus 2308 | LOVHK is able to phosphotransfer to the central regulator of the GSR system in Brucella, specific interaction with its cognate response regulators | ? | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Brucella abortus | Q2YKK7 | - |
- |
Brucella abortus 2308 | Q2YKK7 | - |
- |
Posttranslational Modification | Comment | Organism |
---|---|---|
phosphoprotein | activation of LOVHK by blue-light increases the autophosphorylation activity of the HK domain of the histidine kinase | Brucella abortus |
Purification (Comment) | Organism |
---|---|
recombinant His-tagged LOVHK from Escherichia coli strain BL21(DE3) by nickel affinity chromatography | Brucella abortus |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
ATP + protein L-histidine | - |
Brucella abortus | ADP + protein N-phospho-L-histidine | - |
? | |
ATP + protein L-histidine | - |
Brucella abortus 2308 | ADP + protein N-phospho-L-histidine | - |
? | |
additional information | LOVHK is able to phosphotransfer to the central regulator of the GSR system in Brucella, specific interaction with its cognate response regulators | Brucella abortus | ? | - |
? | |
additional information | LOVHK is able to phosphotransfer to the central regulator of the GSR system in Brucella, specific interaction with its cognate response regulators | Brucella abortus 2308 | ? | - |
? |
Synonyms | Comment | Organism |
---|---|---|
BA-LOV-histidine kinase | UniProt | Brucella abortus |
BA-LOV-HK | UniProt | Brucella abortus |
BAB2_0652 | - |
Brucella abortus |
blue-light-activated histidine kinase | UniProt | Brucella abortus |
LOV | - |
Brucella abortus |
LOVHK | - |
Brucella abortus |
Cofactor | Comment | Organism | Structure |
---|---|---|---|
ATP | - |
Brucella abortus | |
additional information | LOV domains are blue-light sensory modules which bind a flavin molecule as cofactor. Activation of LOVHK by blue-light increases the autophosphorylation activity of the HK domain | Brucella abortus |
General Information | Comment | Organism |
---|---|---|
evolution | Brucella spp. genomes encode a LOV-domain-containing protein that is associated to a PAS (Per, Arnt and Sim) domain plus a HK domain (LOVHK), which belongs to the HWE family | Brucella abortus |
malfunction | in the absence of LOVHK the expression of the virB operon is downregulated. LOVHK plays a role in the intracellular survival of Brucella, since deletion of this gene in Brucella abortus shows an attenuated phenotype in cell-culture infection assays. PhyR expression is decreased in the lovhk mutant | Brucella abortus |
additional information | LOV domains are blue-light sensory modules which bind a flavin molecule as cofactor | Brucella abortus |
physiological function | LOV histidine kinase positively regulates the general stress response system and affects the virB operon expression in Brucella abortus. The Brucella genome encodes a sensor histidine kinase containing a LOV domain upstream from the kinase, LOVHK, which plays an important role in light-regulated Brucella virulence. The intracellular signaling pathway is initiated by the light sensor LOVHK, which functionally interacts with two response regulators: PhyR and LovR, constituting a functional two-component signal-transduction system. LOVHK contributes to the activation of the general stress response (GSR) system in Brucella via PhyR, the main regulator of the general stress response system, while LovR is proposed to be a phosphate-sink for LOVHK, decreasing its phosphorylation state. LOVHK plays a role in the intracellular survival of Brucella and in defense of stress induced by starvation. LOVHK signaling cascade, overview | Brucella abortus |