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CTD recovery

CTD recovery

Niskins

Niskins

Incubations @ KOK1507

Incubations @ KOK1507

Incubations @ KOK1507

Incubations @ KOK1507

Workspace @ KOK1507

Workspace @ KOK1507

Workspace @ KOK1507

Workspace @ KOK1507

Incubation array @ KOK1507

Incubation array @ KOK1507

Incubation array @KOK1507

Incubation array @KOK1507

CARD-FISH filtration zone @ KOK1507

CARD-FISH filtration zone @ KOK1507

CARD-FISH filtration zone @ KOK1507

CARD-FISH filtration zone @ KOK1507

Filtering @ KOK1507

Filtering @ KOK1507

Buttoned up for the transit to ALOHA

Buttoned up for the transit to ALOHA

Incubation array @ KOK1507

Incubation array @ KOK1507

Recovering the Array @KOK1507

Recovering the Array @KOK1507

MEGAMER BD Influx Cytometer

MEGAMER BD Influx Cytometer

KOK1597 Incubation Array Deployment

KOK1597 Incubation Array Deployment

KOK1507 Filtering Station

KOK1507 Filtering Station

KOK1507

KOK1507

R/V KOK

R/V KOK

KOK1507 Sunset

KOK1507 Sunset

KOK1507 Diamond Head

KOK1507 Diamond Head

KOK1507 Sunset

KOK1507 Sunset

KOK1507 Sunrise

KOK1507 Sunrise

KOK1507 Incubation Array Recovery

KOK1507 Incubation Array Recovery

KOK1507 Incubation Array Deployment

KOK1507 Incubation Array Deployment

KOK1507

KOK1507

CMORE C-20 CTD deployment

CMORE C-20 CTD deployment

CMORE C-20 CTD deployment

CMORE C-20 CTD deployment

CMORE C-20 qPCR

CMORE C-20 qPCR

CMORE C-20 CTD deployment

CMORE C-20 CTD deployment

CMORE C-20 CTD sampling

CMORE C-20 CTD sampling

CMORE C-20 CTD deployment

CMORE C-20 CTD deployment

R/V Atlantis, Iquique, Chile 2010

R/V Atlantis, Iquique, Chile 2010

Deckboard Incubations, ETSP

Deckboard Incubations, ETSP

Sunset, ETSP

Sunset, ETSP

R/V Atlantis, ETSP

R/V Atlantis, ETSP

Dusk, ETSP

Dusk, ETSP

CTD Rosette, R/V Atlantis

CTD Rosette, R/V Atlantis

Filtering Station, R/V Atlantis

Filtering Station, R/V Atlantis

CTD Deployment, R/V Atlantis

CTD Deployment, R/V Atlantis

View from the bridge, R/V Atlantis

View from the bridge, R/V Atlantis

CTD recovery, R/V Atlantis

CTD recovery, R/V Atlantis

Sunset, ETSP

Sunset, ETSP

Sunset, ETSP

Sunset, ETSP

ESP Recovery, R/V Kilo Moana, 2011

ESP Recovery, R/V Kilo Moana, 2011

ESP Recovery, R/V Kilo Moana, 2011

ESP Recovery, R/V Kilo Moana, 2011

ESP Recovery, R/V Kilo Moana, 2011

ESP Recovery, R/V Kilo Moana, 2011

ESP, NPSG, 2011

ESP, NPSG, 2011

ESP, R/V Kilo Moana, 2011

ESP, R/V Kilo Moana, 2011

Snug Harbor, Feb. 2015

Snug Harbor, Feb. 2015

Oahu, Feb. 2015

Oahu, Feb. 2015

Returning from Station ALOHA, 2015

Returning from Station ALOHA, 2015

Hand lining for Mahi Mahi, R/V KoK

Hand lining for Mahi Mahi, R/V KoK

Karl (UH) Cytometry Van, R/V KoK

Karl (UH) Cytometry Van, R/V KoK

R/V KoK, Station ALOHA, Feb. 2015

R/V KoK, Station ALOHA, Feb. 2015

R/V KOK @ Stn. ALOHA, Feb. 2015

R/V KOK @ Stn. ALOHA, Feb. 2015

Deckboard incubations, HOT 269

Deckboard incubations, HOT 269

Deckboard incubations, HOT 269

Deckboard incubations, HOT 269

Submarine sighting off Oahu

Submarine sighting off Oahu

Departing Oahu, HOT 269, Feb. 2015

Departing Oahu, HOT 269, Feb. 2015

HOT 269 departing from Snug Harbor

HOT 269 departing from Snug Harbor

Sunrise departure, HOT 269

Sunrise departure, HOT 269

R/V Ka`imikai-o-Kanaloa, Feb. 2105

R/V Ka`imikai-o-Kanaloa, Feb. 2105

Science team, NEMO Cruise, Aug. 2014

Science team, NEMO Cruise, Aug. 2014

Snug Harbor, Oahu

Snug Harbor, Oahu

Storm in the NPSG, BioLINCs, 2011

Storm in the NPSG, BioLINCs, 2011

Julie Robidart, Chief Sci. BioLINCS

Julie Robidart, Chief Sci. BioLINCS

Sunset in the NPSG, BioLINCs, 2011

Sunset in the NPSG, BioLINCs, 2011

Sunset in the NPSG, BioLINCs, 2011

Sunset in the NPSG, BioLINCs, 2011

ESP Recovery, BioLINCs, 2011

ESP Recovery, BioLINCs, 2011

ESP Recovery, BioLINCs, 2011

ESP Recovery, BioLINCs, 2011

ESP Recovery, BioLINCs, 2011

ESP Recovery, BioLINCs, 2011

Sunset, NPSG, R/V Kilo Moana, 2011

Sunset, NPSG, R/V Kilo Moana, 2011

SID Deployment, BioLINCs, 2011

SID Deployment, BioLINCs, 2011

Waiting for the ESP, BioLINCs, 2011

Waiting for the ESP, BioLINCs, 2011

Deniz Bombar, BioLINCs, 2011

Deniz Bombar, BioLINCs, 2011

Ariel Rabines, BioLINCs, 2011

Ariel Rabines, BioLINCs, 2011

Tense ESP recovery, BioLINCs, 2011

Tense ESP recovery, BioLINCs, 2011

Jon & Darwin

Jon & Darwin

Jon & Darwin

Jon & Darwin

Britt @ microscope

Britt @ microscope

cultures

cultures

Jon

Jon

Mari, Hanna, Britt & Jon

Mari, Hanna, Britt & Jon

Mari, Hanna, Britt & Jon

Mari, Hanna, Britt & Jon

heading to sea

heading to sea

departing sung harbor

departing sung harbor

women @ sea

women @ sea

safety @ sea

safety @ sea

CTD recovery

CTD recovery

CTD recovery

CTD recovery

ready to deploy in situ array

ready to deploy in situ array

in situ array recovery

in situ array recovery

in situ array recovery

in situ array recovery

in situ array recovery

in situ array recovery

in situ array recovery

in situ array recovery

returning to land

returning to land

sunset

sunset

sunset

sunset

sunset

sunset

sunset

sunset

CTD @ dusk

CTD @ dusk

sunset

sunset

returning to land

returning to land

tug assist

tug assist

3000 m foam cups

3000 m foam cups

Incubation babies lined up

Incubation babies lined up

Incubators on a sunny day

Incubators on a sunny day

Filtering for CARD-FISH in the dead box

Filtering for CARD-FISH in the dead box

Krill

Krill

Sunset

Sunset

Termite in bed

Termite in bed

The team

The team

R/V Sikuliaq

R/V Sikuliaq

Deck Ops R/V Sproul

Deck Ops R/V Sproul

Winch

Winch

Deployed!

Deployed!

Winch R/V Sproul

Winch R/V Sproul

CTD Ops R/V Sproul

CTD Ops R/V Sproul

Incubators R/V Sproul

Incubators R/V Sproul

Goofin'

Goofin'

SP1714 team

SP1714 team

Brittany

Brittany

UCSC team SP1727

UCSC team SP1727

CTD ops R/V Sproul

CTD ops R/V Sproul

Looking for land

Looking for land

Hardy little qPCR

Hardy little qPCR

Incubations!

Incubations!

Nome, AK

Nome, AK

Nome, AK

Nome, AK

Sikuliaq on the hook in Nome

Sikuliaq on the hook in Nome

Baltic Room

Baltic Room

Beaufort Sea

Beaufort Sea

Beaufort Sea Sunset

Beaufort Sea Sunset

R/V Ukpik, Barrow, AK

R/V Ukpik, Barrow, AK

Barrow, AK

Barrow, AK

R/V Ukpik

R/V Ukpik

BARC

BARC

SIO

SIO

SP1727

SP1727

SP1727

SP1727

Zehr Laboratory

Research in our laboratory group focuses on how microorganisms control the availability of nitrogen, a critical element in all life as we know it. Nitrogen, a major plant nutrient, is transformed from one form to another by microorganisms, and moves between habitats. A large reservoir of nitrogen on Earth resides in the air we breath: 80% of the atmosphere is nitrogen gas. Nitrogen gas, or dinitrogen (2 nitrogen atoms triple bonded together) is unavailable to most organisms, in particular the eukaryotic plants and animals. Many diverse prokaryotic microorganisms have the ability to fix nitrogen from the atmosphere into a biologically available form. Biological nitrogen fixation is catalyzed by an enzyme, called nitrogenase. Since most of the microorganisms in the natural environment have yet to be cultivated, we study the microorganisms in the environment that fix nitrogen by looking for the genes and proteins involved in nitrogen fixation.

OUR LATEST RESEARCH

K.A. Turk-Kubo, M.M. Mills, K.R. Arrigo, G. van Dijken, B.A. Henke, B. Stewart, S.T. Wilson, J.P. Zehr, (2021) ISME Communications

M.R. Gradoville, A.M. Cabello, K.A. Turk-Kubo, D.M. Karl, J.P Zehr (2021) Environmental Microbiology

S. Cheung, J.P. Zehr, X. Xia, C. Tsurumoto, H. Endo, S. Nakaoka, W. Mak, K. Suzuki, H. Liu (2021) Environmental Microbiology

D Sarkar, M Landa, A Bandyopadhyay, HB Pakrasi, JP Zehr, CD Maranas (2021) PLoS computational biology

M. Landa, K.A. Turk-Kubo, F.M. Cornejo-Castillo, B.A. Henke, J.P. Zehr (2021) Frontiers in Microbiology

A.M. Cabello, K.A. Turk‐Kubo, K. Hayashi, L. Jacobs, R.M. Kudela, J.P. Zehr (2020) Journal of Phycology

M.M. Mills, K. A. Turk-Kubo, G.L. van Dijken, B.A. Henke, K. Harding, S.T. Wilson, K.R. Arrigo, J.P. Zehr (2020) ISME J.

RECENT RESEARCH CRUISES

Eddy Exploration & Ecosystem Dynamics
North Pacific Subtropical Gyre (NPSG)
Schmidt Ocean Institute
R/V Falkor, March-April 2018

Postdocs Rosie Gradoville and Ana Maria Cabello joined researchers from SCOPE and MBARI to on a research cruise focused on understanding how meso-scale processes (eddies) influence micro-scale processes (diazotroph activity). 

Check out the cruise blog here

Coastal California/Baja Mexico, R/V Sproul, October 2017

Researchers from UCSC and Stanford recently led an expedition to study the activity of UCYN-A in a coastal shelf ecosystem, in collaboration with researchers from VIMS and UABC. 

Our research is supported by the Simons Foundation, National Science Foundation (NSF), the Gordon and Betty Moore Foundation (GBMF), and Co-funded by the Horizon 2020 Framework Programme of the European Union.

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