scholarly journals Transposon Mutagenesis Identified Chromosomal and Plasmid Genes Essential for Adaptation of the Marine Bacterium Dinoroseobacter shibae to Anaerobic Conditions

2013 ◽  
Vol 195 (20) ◽  
pp. 4769-4777 ◽  
Author(s):  
M. Ebert ◽  
S. Laass ◽  
M. Burghartz ◽  
J. Petersen ◽  
S. Kossmehl ◽  
...  
Keyword(s):  
Marine Bacterium ◽  
Transposon Mutagenesis ◽  
Anaerobic Conditions ◽  
Dinoroseobacter Shibae ◽  
Plasmid Genes

Energy coupling to K+ transport in a marine bacterium

1980 ◽  
Vol 58 (10) ◽  
pp. 1206-1214 ◽  
Author(s):  
Edward G. Sedgwick ◽  
Robert A. MacLeod
Keyword(s):  
Driving Force ◽  
Maximum Rate ◽  
Marine Bacterium ◽  
Energy Coupling ◽  
Strictly Aerobic ◽  
Proton Release ◽  
Anaerobic Conditions ◽  
Intact Cells ◽  
Absorbing Material ◽  
K Transport

Cells of the marine bacterium Alteromonas haloplanktis 214 ATCC 19855 (previously referred to as marine pseudomonad B-16) were depleted of K+ by washing with 0.1 M MgSO4. Washing with 0.05 M MgSO4 lowered the Vmax for K+ transport compared with washing with 0.1 M but did not change the Km, while washing with lower concentrations of MgSO4 caused loss of ultraviolet-absorbing material from the cells. K+ uptake was a strictly aerobic process and was accompanied by proton release. When an anaerobic suspension of cells was added to incubation mixtures containing increasing amounts of O2, intracellular ATP concentrations increased as the O2 concentration increased and reached near maximum values before K+ transport began. The O2 concentration initiating K+ transport caused transport to proceed at its maximum rate. For these experiments A. haloplanktis was depleted of ATP by incubating under anaerobic conditions. Incubating with either N′,N′-dicyclohexyl carbodiimide (DCCD) or arsenate failed to deplete intact cells of ATP or prevent K+ transport. The inhibitory activity of DCCD for ATPase in membrane preparations was higher at 5 mM than at other MgSO4 concentrations and increased with time. Cyanide and the uncoupling agents tetrachlorosalicylanide (TCS) and carbonylcyanide p-trifluoromethoxyphenylhydrazone (FCCP) prevented K+ uptake while TCS and FCCP though not cyanide caused K+ to be released from K+-containing cells. It is concluded that the driving force for K+ transport in these cells is likely to be the membrane potential and that K+ transport may be gated.

scholarly journals Arcobacter marinus sp. nov.

2010 ◽  
Vol 60 (3) ◽  
pp. 531-536 ◽  
Author(s):  
Hye Min Kim ◽  
Chung Yeon Hwang ◽  
Byung Cheol Cho
Keyword(s):  
16S Rrna ◽  
Marine Bacterium ◽  
Novel Species ◽  
Phylogenetic Analyses ◽  
Distinct Species ◽  
Gene Sequences ◽  
Anaerobic Conditions ◽  
Microaerobic Conditions ◽  
Curved Rod ◽  
Sequence Similarities

A slightly curved, rod-shaped marine bacterium, designated strain CL-S1T, was isolated from near Dokdo, an island in the East Sea, Korea. Cells were Gram-negative and grew well under either aerobic or microaerobic conditions. Analyses of the 16S rRNA and gyrA gene sequences of strain CL-S1T revealed an affiliation with the genus Arcobacter within the class Epsilonproteobacteria. Phylogenetic analyses based on 16S rRNA and gyrA gene sequences showed that strain CL-S1T formed a robust clade with Arcobacter halophilus LA31BT, with sequence similarities of 96.1 and 88.2 %, respectively. DNA–DNA relatedness between strain CL-S1T and A. halophilus DSM 18005T was 44 %, indicating that they represent genomically distinct species. Strain CL-S1T grew optimally at 30–37 °C, at pH 7 and in the presence of 3–5 % NaCl. The dominant cellular fatty acids were iso-C15 : 0 2-OH and/or C16 : 1 ω7c (28.4 %), C16 : 0 (26.2 %) and C18 : 1 ω7c (22.3 %). The DNA G+C content of strain CL-S1T was 28 mol%. Strain CL-S1T differed phenotypically from A. halophilus LA31BT based on its ability to grow aerobically at 10 °C and inability to grow under anaerobic conditions. Based on the data presented, strain CL-S1T is considered to represent a novel species of the genus Arcobacter, for which the name Arcobacter marinus sp. nov. is proposed. The type strain is CL-S1T (=KCCM 90072T =JCM 15502T).

scholarly journals Transcriptional response of the photoheterotrophic marine bacterium Dinoroseobacter shibae to changing light regimes

2011 ◽  
Vol 5 (12) ◽  
pp. 1957-1968 ◽  
Author(s):  
Jürgen Tomasch ◽  
Regina Gohl ◽  
Boyke Bunk ◽  
Maria Suarez Diez ◽  
Irene Wagner-Döbler
Keyword(s):  
Marine Bacterium ◽  
Transcriptional Response ◽  
Light Regimes ◽  
Dinoroseobacter Shibae ◽  
Changing Light

TEM study of a biofilm on copper corrosion

1996 ◽  
Vol 54 ◽  
pp. 220-221
Author(s):  
W. A. Chiou ◽  
N. Kohyama ◽  
B. Little ◽  
P. Wagner ◽  
M. Meshii
Keyword(s):  
Marine Bacterium ◽  
Culture Medium ◽  
Copper Alloys ◽  
Pure Copper ◽  
Localized Corrosion ◽  
Natural Seawater ◽  
Copper Corrosion ◽  
New Approach ◽  
The Past ◽  
Copper Tolerant

The corrosion of copper and copper alloys in a marine environment is of great concern because of their widespread use in heat exchangers and steam condensers in which natural seawater is the coolant. It has become increasingly evident that microorganisms play an important role in the corrosion of a number of metals and alloys under a variety of environments. For the past 15 years the use of SEM has proven to be useful in studying biofilms and spatial relationships between bacteria and localized corrosion of metals. Little information, however, has been obtained using TEM capitalizing on its higher spacial resolution and the transmission observation of interfaces. The research presented herein is the first step of this new approach in studying the corrosion with biological influence in pure copper.Commercially produced copper (Cu, 99%) foils of approximately 120 μm thick exposed to a copper-tolerant marine bacterium, Oceanospirillum, and an abiotic culture medium were subsampled (1 cm × 1 cm) for this study along with unexposed control samples.

The Reaction of Thiol Compounds with the Vitamin-K Dependent Clotting Factors

1969 ◽  
Vol 21 (03) ◽  
pp. 573-579 ◽  
Author(s):  
P Fantl
Keyword(s):  
Prothrombin Time ◽  
Vitamin K ◽  
Anaerobic Conditions ◽  
Clotting Factors ◽  
Thiol Compounds ◽  
Aerobic Conditions ◽  
One Stage ◽  
Factor Ii ◽  
Ph Dependent ◽  
The One

SummaryTreatment of human and dog oxalated plasma with 0.2 to 1.0 × 10−1 M 2.3-dithiopropanol (BAL) or dithiothreitol (DTT) at 2–4° C for 30 min results in the reduction of the vitamin-K dependent clotting factors II, VII, IX and X to the respective-SH derivatives. The reaction is pH dependent. Under aerobic conditions the delayed one stage prothrombin time can be partly reversed. Under anaerobic conditions a gradual prolongation of the one stage prothrombin time occurs without reversal.In very diluted plasma treated with the dithiols, prothrombin can be converted into thrombin if serum as source of active factors VII and X is added. In contrast SH factors VII, IX and X are inactive in the specific tests. Reoxidation to active factors II, VII, IX and X takes place during adsorption and elution of the SH derivatives. The experiments have indicated that not only factor II but also factors VII, IX and X have active-S-S-centres.

METABOLISM OF 17α-HYDROXYPROGESTERONE-4-14C-17α-CAPROATE BY HOMOGENATES OF RAT LIVER AND HUMAN PLACENTA

1961 ◽  
Vol 36 (4) ◽  
pp. 511-519 ◽  
Author(s):  
Margaret Wiener ◽  
Charles I. Lupa ◽  
E. Jürgen Plotz
Keyword(s):  
Rat Liver ◽  
Human Placenta ◽  
Steric Hindrance ◽  
Placental Tissue ◽  
Caproic Acid ◽  
Major Product ◽  
Side Chain ◽  
Anaerobic Conditions ◽  
Prolonged Action ◽  
Long Acting

ABSTRACT 17α-hydroxyprogesterone-4-14C-17α-caproate (HPC), a long-acting progestational agent, was incubated with homogenates of rat liver and human placenta. The rat liver was found to reduce Ring A of HPC under anaerobic conditions to form allopregnane-3β,17α-diol-20-one-17α-caproate and pregnane-3β,17α-diol-20-one-17α-caproate, the allopregnane isomer being the major product. The caproic acid ester was neither removed nor altered during the incubation. Placental tissue did not attack HPC under conditions where the 20-ketone of progesterone was reduced. It is postulated that this absence of attack on the side chain is due to steric hindrance from the caproate ester, and that this may account for the prolonged action of HPC.

Sign in / Sign up

Export Citation Format

Share Document