Name: sulfur cycling through microbial reactions
Uploaded: 2026-03-12T13:57:43.000Z
Duration: 1 min 29 s
Channel: JoVE

무기황은 황산염, 원소 황, 황화물 형태로 환경 속을 순환합니다.화산과 열수 분출구는 황화수소와 같은 황 가스를 방출하여 황 순환에 중요한 역할을 합니다.예를 들어, 열수 분출구 근처의 무산소 유기물 풍부한 환경에서는 황산염 환원 박테리아가 주로 황산염을 황화수소로 전환합니다.이 가스는 대부분의 생명체에게 독성이 있지만, 다양한 미생물에 의해 덜 해로운 황산염이나 원소 황으로 전환됩니다.산소가 풍부한 환경에서는 티오바실러스 와 같은 황산화 박테리아가 황화수소를 황 또는 황산염으로 전환하며, 때로는 황산을 형성하고 국소 pH를 낮춥니다.반면, 녹색과 보라색 황 박테리아는 황화물을 황 과립으로 전환시키며, 티오마르가리타 및 유사 미생물이 이를 황산염으로 산화시킵니다.원소 황은 특수 혐기성 박테리아와 고세균에 의해 황화물로 환원될 수 있습니다.무기 변환 외에도, 해조류는 휘발성 유기 황 화합물인 디메틸 황화물을 형성하며, 이는 대기 중 에어로졸로 전환되어 구름 형성을 촉진하고 지구 기후 조절에 도움을 줍니다.

미생물과 황 순환

Microbes and the Sulfur Cycle

황은 지구의 생지화학 시스템에서 중요한 원소입니다. 황산염(SO₄²⁻), 원소 황(S⁰), 황화물(S²⁻) 등 다양한 무기 상태를 거칩니다. 산소와 무산소 환경 전반에 걸친 비생물적·생물학적 메커니즘이 이러한 변형을 복잡하게 매개합니다. 황산염은 황 중 가장 산화된 형태로, 주로 암석, 해양 퇴적물, 해양 해역에 저장되어 전 세계 황 순환에서 장기 저장소 역할을 합니다.산소 환경에서 티오바실러스 속과 같은 화학상가영양균이 환원 황 화합물의 산화를 촉매합니다. 황화물(H₂S)은 화산 분출 또는 열수 배출에서 유래하여 생물학적으로 산화되어 원소 황과 황산염으로 변환됩니다. 반대로 무산소 상태에서는 Desulfovibrio spp.와 같은 황산염 환원 박테리아(SRB)가 분리성 황산염 환원을 수행합니다. 이 혐기성 과정은 아황산염(SO₃²⁻)을 주요 중간체로 사용하여 황산염을 황화물로 환원시키며, 종종 유기 탄소 산화와 결합됩니다.녹색 및 보라색 황 박테리아를 포함한 무산소성 광영양 생물은 황화물을 세포 내 황 과립으로 산화시킵니다. 이 과립들은 티오마르가리타 속과 같은 대형 화학영양 박테리아에 의해 황산염으로 산화되며, 산화 과정에서 양성자를 방출하여 산성화에 기여합니다. 열수 분출구 생태계에서는 황산화 화학자수영양생물이 황화물에서 에너지를 이용해 이산화탄소를 고정하며, 심해 서식지에서 복잡한 미생물 및 동물 군집을 지원합니다.해양 식물성 플랑크톤은 삼투압을 조절하기 위해 디메틸설포니오프로피오네이트(DMSP)를 방출합니다. DMSP의 박테리아 절단은 대기 중으로 진입하는 휘발성 화합물인 디메틸설파이드(DMS)를 생성합니다. DMS의 광산화는 황산염 에어로졸을 생성하며, 이는 구름 응축과 대기 황 침착에 육상 생태계에 영향을 미칩니다. 궁극적으로 식물과 미생물은 시스테인과 메티오닌 같은 황 함유 아미노산을 합성하면서 이 황산염을 동화시키고 환원하여 이 순환을 완성합니다.

Sulfur is a vital element in Earth's biogeochemical systems. It transitions through various inorganic states, including sulfate (SO&#8324;&#178;&#8315;), ...

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Education

교육

JoVE Core

Microbiology

미생물학

Unit

단위

Microbial Ecology

미생물 생태학

KEY TERMS AND CONCEPTS

주요 용어 및 개념

sulfur cycling through microbial reactions

Sulfur cycling depends on microbial reactions that move sulfur through rocks, water, soil, and the air. In Earth systems, sulfur shifts among inorganic forms such as sulfate, elemental sulfur, and sulfide. These changes happen through both abiotic processes and biological activity in oxic and anoxic environments.

Sulfate is the most oxidized form of sulfur. It is stored mainly in rocks, marine sediments, and ocean water, where it acts as a long-term reservoir in the global sulfur cycle. In oxygen-rich settings, chemolithoautotrophic bacteria such as Thiobacillus spp. oxidize reduced sulfur compounds.

Sulfide, often present as H2S, can come from volcanic outgassing or hydrothermal emissions. Microbes can oxidize this sulfide into elemental sulfur and then into sulfate. In oxygen-free environments, sulfate-reducing bacteria such as Desulfovibrio spp. carry out dissimilatory sulfate reduction, which converts sulfate to sulfide through sulfite as an intermediate and is often linked to organic carbon oxidation.

Some microbes use sulfur in light-filled but low-oxygen habitats. Green and purple sulfur bacteria, which are anoxygenic phototrophs, oxidize sulfide and store the sulfur as intracellular granules. Large chemolithotrophic bacteria such as Thiomargarita spp. can then oxidize these granules further to sulfate. This process releases protons and can make the surrounding environment more acidic.

Sulfur cycling also powers life at hydrothermal vents. There, sulfur-oxidizing chemoautotrophs use energy from sulfide to fix carbon dioxide. Their activity supports complex microbial and animal communities in deep-sea ecosystems.

Sulfur also moves through the atmosphere. Marine phytoplankton release dimethylsulfoniopropionate, or DMSP, to help control osmotic pressure. Bacteria break DMSP down into dimethylsulfide, or DMS, a volatile gas that enters the atmosphere. Sunlight then photooxidizes DMS into sulfate aerosols, which affect cloud formation and sulfur deposition on land. Plants and microbes take up this sulfate and reduce it while making sulfur-containing amino acids such as cysteine and methionine, completing the cycle.

Sulfur Cycling Through Microbial Reactions

sulfur-cycling-through-microbial-reactions

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key terms and concepts

Explore how microbes move sulfur through sulfate, sulfide, and sulfur granules in oxic, anoxic, and marine environments across the sulfur cycle.

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microbiology

Sulfur Cycling Through Microbial Reactions

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