Johnson Michael S, Burns Brendan P, Herdean Andrei, Angeloski Alexander, Ralph Peter, Morris Therese, Kindler Gareth, Wong Hon Lun, Kuzhiumparambil Unnikrishnan, Sedger Lisa M, Larkum Anthony W D
School of Medical Sciences, University of New South Wales, Sydney 2052, Australia.
School of Life Sciences, University of Technology Sydney, Sydney 2007, Australia.
Microorganisms. 2022 May 17;10(5):1035. doi: 10.3390/microorganisms10051035.
The genus is unique among phototrophic organisms due to the dominance of chlorophyll in its photosynthetic reaction centres and light-harvesting proteins. This allows to capture light energy for photosynthesis over an extended spectrum of up to ~760 nm in the near infra-red (NIR) spectrum. sp. has been reported in a variety of ecological niches, ranging from polar to tropical shallow aquatic sites. Here, we report a new strain isolated from an NIR-enriched stratified microbial layer 4-6 mm under the surface of stromatolite mats located in the Hamelin Pool of Shark Bay, Western Australia. Pigment analysis by spectrometry/fluorometry, flow cytometry and spectral confocal microscopy identifies unique patterns in pigment content that likely reflect niche adaption. For example, unlike the original species (type strain MBIC11017), this new strain, , shows little change in the chlorophyll in response to changes in light wavelength, displays a different Fv/Fm response and lacks detectable levels of phycocyanin. Indeed, 16S rRNA analysis supports the identity of the LARK001 strain as close to but distinct from from the HICR111A strain first isolated from Heron Island and previously found on the Great Barrier Reef under coral rubble on the reef flat. Taken together, LARK001 is a new cyanobacterial strain adapted to the stromatolite mats in Shark Bay.
由于叶绿素在其光合反应中心和捕光蛋白中占主导地位，该属在光合生物中独一无二。这使得其能够在近红外（NIR）光谱中高达约760 nm的扩展光谱范围内捕获光能用于光合作用。已在从极地到热带的各种浅水生境中报道过该属物种。在此，我们报告了一种新的该属菌株，它是从位于西澳大利亚鲨鱼湾哈梅林池叠层石垫表面以下4 - 6毫米处富含近红外光的分层微生物层中分离出来的。通过光谱法/荧光法、流式细胞术和光谱共聚焦显微镜进行的色素分析确定了色素含量中的独特模式，这些模式可能反映了生态位适应性。例如，与原始物种（模式菌株MBIC11017）不同，这种新菌株对光波长变化时叶绿素a几乎没有变化，显示出不同的Fv/Fm反应，并且检测不到藻蓝蛋白水平。实际上，16S rRNA分析支持LARK001菌株与首次从赫伦岛分离且先前在大堡礁礁坪珊瑚碎石下发现的HICR111A菌株相近但不同。综合来看，LARK001是一种适应鲨鱼湾叠层石垫的新蓝藻菌株。
