Photoactivated adenylyl cyclase

Structure of the photoactivated adenylyl cyclase OaPAC forming a homodimer. FMN: flavin mononucleotide, the light-absorbing pigment. [1]

Photoactivated adenylyl cyclase (PAC) is a protein consisting of an adenylyl cyclase enzyme domain directly linked to a BLUF (blue light receptor using FAD) type light sensor domain. When illuminated with blue light, the enzyme domain becomes active and converts ATP to cAMP, an important second messenger in many cells. In the unicellular flagellate Euglena gracilis, PACα and PACβ (euPACs) serve as a photoreceptor complex that senses light for photophobic responses and phototaxis.[2] Small but potent PACs were identified in the genome of the bacteria Beggiatoa (bPAC) and Oscillatoria acuminata (OaPAC).[3][1] While natural bPAC has some enzymatic activity in the absence of light, variants with no dark activity have been engineered (PACmn).[4]

  1. ^ a b Ohki, Mio; Sugiyama, Kanako; Kawai, Fumihiro; Tanaka, Hitomi; Nihei, Yuuki; Unzai, Satoru; Takebe, Masumi; Matsunaga, Shigeru; Adachi, Shin-ichi; Shibayama, Naoya; Zhou, Zhiwen (2016-05-31). "Structural insight into photoactivation of an adenylate cyclase from a photosynthetic cyanobacterium". Proceedings of the National Academy of Sciences. 113 (24): 6659–6664. Bibcode:2016PNAS..113.6659O. doi:10.1073/pnas.1517520113. ISSN 0027-8424. PMC 4914150. PMID 27247413.
  2. ^ Iseki, Mineo; Matsunaga, Shigeru; Murakami, Akio; Ohno, Kaoru; Shiga, Kiyoshi; Yoshida, Kazuichi; Sugai, Michizo; Takahashi, Tetsuo; Hori, Terumitsu; Watanabe, Masakatsu (2002-02-28). "A blue-light-activated adenylyl cyclase mediates photoavoidance in Euglena gracilis". Nature. 415 (6875): 1047–1051. Bibcode:2002Natur.415.1047I. doi:10.1038/4151047a. ISSN 1476-4687. PMID 11875575. S2CID 4420996.
  3. ^ Stierl, Manuela; Stumpf, Patrick; Udwari, Daniel; Gueta, Ronnie; Hagedorn, Rolf; Losi, Aba; Gärtner, Wolfgang; Petereit, Linda; Efetova, Marina; Schwarzel, Martin; Oertner, Thomas G. (2011-01-14). "Light Modulation of Cellular cAMP by a Small Bacterial Photoactivated Adenylyl Cyclase, bPAC, of the Soil Bacterium Beggiatoa". Journal of Biological Chemistry. 286 (2): 1181–1188. doi:10.1074/jbc.M110.185496. ISSN 0021-9258. PMC 3020725. PMID 21030594.
  4. ^ Yang, Shang; Constantin, Oana M.; Sachidanandan, Divya; Hofmann, Hannes; Kunz, Tobias C.; Kozjak-Pavlovic, Vera; Oertner, Thomas G.; Nagel, Georg; Kittel, Robert J.; Gee, Christine E.; Gao, Shiqiang (2021-10-18). "PACmn for improved optogenetic control of intracellular cAMP". BMC Biology. 19 (1): 227. doi:10.1186/s12915-021-01151-9. ISSN 1741-7007. PMC 8522238. PMID 34663304.