{{Short description|Cyanobacteria strain}} {{More citations needed|date=June 2025}} {{Use dmy dates|date=June 2025}} {{Infraspeciesbox special | image = | image_caption = | genus = Cyanobacterium | species = aponinum | infraspecies_rank1_name = Strain | infraspecies_rank1 = UTEX 3222 | synonyms = ''Cyanobacterium aponinum'' var. "Vulcano 2" | synonyms_ref = <ref>Algae, UTEX Culture Collection of. "UTEX B 3222 ''Cyanobacterium aponinum''". UTEX Culture Collection of Algae. Retrieved 1 March 2025.</ref> }}

'''UTEX 3222''' is a strain of the species ''Cyanobacterium aponinum'', that was discovered off the coast of Baia di Levante, Italy.<ref name=":0">{{Cite journal |last1=Schubert |first1=Max G. |last2=Tang |first2=Tzu-Chieh |last3=Goodchild-Michelman |first3=Isabella M. |last4=Ryon |first4=Krista A. |last5=Henriksen |first5=James R. |last6=Chavkin |first6=Theodore |last7=Wu |first7=Yanqi |last8=Miettinen |first8=Teemu P. |last9=Van Wychen |first9=Stefanie |last10=Dahlin |first10=Lukas R. |last11=Spatafora |first11=Davide |last12=Turco |first12=Gabriele |last13=Guarnieri |first13=Michael T. |last14=Manalis |first14=Scott R. |last15=Kowitz |first15=John |date=20 November 2024 |editor-last=Cann |editor-first=Isaac |title=Cyanobacteria newly isolated from marine volcanic seeps display rapid sinking and robust, high-density growth |journal=Applied and Environmental Microbiology |language=en |volume=90 |issue=11 |pages=e0084124 |doi=10.1128/aem.00841-24 |pmid=39470214 |pmc=11577773 |bibcode=2024ApEnM..90E.841S |issn=0099-2240}}</ref> This cyanobacteria exhibits fast, high density, unicellular, planktonic growth while displaying quick settling rates in liquid.<ref name=":0" /> With the addition of its cyanobacterial photosynthetic function and its high carbon biomass composition, UTEX 3222 seems potentially useful for atmospheric CO<sub>2</sub> sequestration and optimizing bioproduction within industry.<ref name=":0" />

==Characteristics== UTEX 3222 demonstrates fast growth on solid, BG-11 freshwater medium, with a wide tolerance for growing conditions.<ref name=":0" /> Optimal growth rate has been achieved at a temperature of 45&nbsp;°C, a temperature somewhat higher than used for other cyanobacteria models.<ref name=":0" /> A pH of 6.5-9.8 was tolerated by UTEX 3222 with the fastest exponential growth found at pH 6.5 and highest cell density at pH 8.<ref name=":0" /> Moderate salinity (10g/L NaCL) produced fastest growth, yet UTEX 3222 exhibited high salt tolerance. In addition, an irradiance of 1,500 μE is tolerated but growth rates reach capacity at 500 μE.<ref name=":0" /> In optimal conditions, UTEX 3222 has displayed a fast doubling time of 2.35 ± 0.10 hours.<ref name=":0" /> As well, UTEX 3222 grows to high density (>31 g/L biomass dry weight after 12 days) in batch culture, producing larger colonies than record setting UTEX 3154.<ref name=":0" />

=== Biomass characterization === Extracellular polysaccharides (EPS) and storage granules are common carbon storage structures within cyanobacteria.<ref name=":0" /> These structures appear more prominent in size and number in UTEX 3222, compared to the high-density growing cyanobacteria, UTEX 3154.<ref name=":0" /> These structural differences account for UTEX 3222's higher carbon content as revealed in biomass composition analysis and C/H/N elemental analysis.<ref name=":0" />

== Phenotype == In liquid cultures, UTEX 3222 aggregates into tight pellets within hours and settles quickly. The biomass of UTEX 3222 settles faster than the comparison strain, UTEX 3154, with a gravitational sinking velocity 2.16x quicker.<ref name=":0" /> The difference in sinking velocity is primarily due to UTEX 3222's greater cell volume rather than buoyant density.<ref name=":0" /> The dramatic difference in settling overnight and the speed at which UTEX 3222 forms a supernatant, cannot fully be explained by sinking velocity, indicating there are other factors involved such as cell aggregation.<ref name=":0" />

== History == ''Cyanobacterium aponinum'' UTEX 3222 was discovered in 2024 when Schubert et al. explored shallow volcanic seeps off the coast of Baia di Levante in Vulcano Island, Italy.<ref name=":0" /> The team was investigating illuminated marine areas with high CO<sub>2</sub> levels, hoping to find organisms that had evolved enhanced fitness, as adaptations would not need to focus on limitations in CO<sub>2</sub> availability.<ref name=":0" /> The closest known relative to UTEX 3222 is ''Cyanobacterium aponinum'' PCC 10605, yet the whole clade remains relatively unstudied.<ref name=":0" />

==References== {{Reflist}}

Category:Chroococcales