Starvation-Survival of Heterotrophs in the Marine Environment

Morita, Richard Y.

doi:10.1007/978-1-4615-8318-9_5

Cited by 244 publications

(172 citation statements)

References 95 publications

Supporting

Mentioning

162

Contrasting

Unclassified

Order By: Relevance

“…survival (Morita, 1982). Two important aspects of starvation survival are that the copiotrophic organisms must preserve their genomes during prolonged periods of energy and nutrient exhaustion, and also 'retain the ability to quickly metabolize substrates' that sporadically become available (Morita, 1982).…”

Section: Introductionmentioning

confidence: 99%

“…Two important aspects of starvation survival are that the copiotrophic organisms must preserve their genomes during prolonged periods of energy and nutrient exhaustion, and also 'retain the ability to quickly metabolize substrates' that sporadically become available (Morita, 1982). Starvation survival has been described in several marine bacterial strains, including the marine psychrophilic Vibrio Ant-300 (Novitsky & Morita, 1977;Amy et al, 1983a), and the mesophilic Vibrio sp.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Macromolecular synthesis during recovery of the marine Vibrio sp. S14 from starvation

Albertson

Nyström

Kjelleberg

1990

Journal of General Microbiology

View full text Add to dashboard Cite

The recovery of Vibrio sp. S14 cells from energy-and nutrient-starvation was monitored after the addition of glucose minimal medium. Upshift experiments were done throughout a starvation period of 200 h to determine whether cells were more responsive to nutrient addition at the onset of starvation, or if the previously described programme of starvation-induced cellular reorganization had to be completed before cells could become committed to recovery following nutritional upshifts. The kinetics of macromolecular synthesis (RNA, protein and DNA), the rate of respiration and changes in median cell volume in response to nutritional upshifts at different times of starvation were examined. The relative rates of RNA and protein synthesis increased immediately upon addition of glucose minimal medium; the increase in protein synthesis was not dependent on a parallel increase in RNA synthesis, indicating that the starved cells may have an excess of protein synthesizing machinery, including stable RNA and functional ribosom?. The subsequent increase in the rate of DNA replication was initiated approximately 60min before the first apparent cell division at approximately one doubling of the theoretical minimal cell volume ( Vu). Two-dimensional gel electrophoresis was used to demonstrate the fate of starvationspecific proteins during the upshift, and also the synthesis of recovery-induced proteins that were not found in starving cells. Most starvation-inducible proteins were repressed immediately at the onset of the nutritional upshift, while 11 of the 21 recovery-induced proteins identified were expressed exclusively during the maturation phase and were subsequently repressed at the onset of regrowth. The possible role of such maturation-specific proteins in the rapid formation of a reproductive cell committed to growth and division is discussed.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Macromolecular synthesis during recovery of the marine Vibrio sp. S14 from starvation

Albertson

Nyström

Kjelleberg

1990

Journal of General Microbiology

View full text Add to dashboard Cite

show abstract

“…Therefore the hydrolysis of polymeric carbohydrates is generally accepted as the first and ratelimiting step in their mineralization by microheterotrophs (Ring 1986;Billen 1982). Many of these transformations can only be mediated by heterotrophic bacteria since the enzyme systems required are not found in higher organisms (Morita 1982). In spite of the significance of carbohydrate hydrolysis, however, relatively little is known about the patterns and rates of its hydrolysis in situ and of the enzyme systems that are involved.…”

mentioning

confidence: 99%

Characterization and significance of β‐glucosidase activity in lake water

Chróst

1989

Limnology & Oceanography

133

View full text Add to dashboard Cite

Kinetics of P-glucosidase activity (PGlcA) and bacterial activity (glucose uptake, thymidine incorporation) and cell numbers were measured in the euphotic zone and in the water column of PluBsee during spring phytoplankton bloom development and after its breakdown. Heterotrophic bacteria were the major producers of the enzyme. Activity of free &glucosidase, unassociated with microbial cells, was negligible. /3GlcA displayed a distinct temporal and spatial distribution pattern in lake water. @GlcA was low when algal populations grew actively, but during the algal bloom breakdown /3GlcA increased rapidly. The increase in PGlcA was proportional to the abundance of bacteria and to their heterotrophic uptake of glucose, as well as to bacterial production, measured by the thymidine incorporation method. In contrast with its response to pH, /3-glucosidase exhibited no obvious adaptation to ambient temperature of lake water. PGlcA produced by aquatic bacteria was under control of a repression-induction mechanism, and synthesis was derepressed when the level of directly assimilable hexoses (glucose or galactose) fell below a critical level. The tight relationship between the rates of PGlcA and glucose uptake indicated the existence of a specific, coupled hydrolysis-uptake system in lacustrine bacteria.During the past decade increasing numbers of ecological studies have considered the complexity of aquatic environments. One major outcome has been an accelerated interest in the role of bacteria and the mode by which organic matter is made available to them. Heterotrophic bacteria comprise the key level which affects whole-lake metabolism, i.e. nutrient cycles, organic matter transformation and mineralization, and energy flow. The measurements of bacterial activities in natural waters are therefore very important for understanding the pathways and dynamics of carbon flux between various trophic levels in lakes. The metabolic activity of microheterotrophs is also im-' Permanent address:

show abstract

“…Bacterial abundance and cell size each vary with available substrate resources (Morita 1982), with grazing (Giide 1986), with water temperature (Chrzanowski et al 1988), and in association with particles (Simon 1987). The effects of these environmental factors may tend to be offsetting.…”

Section: Acknowledgmentsmentioning

confidence: 99%

Association of turbidity and organic carbon with bacterial abundance and cell size in a large, turbid, tropical lake

Lind

Dávalos‐Lind

1991

Limnol. Oceanogr.

View full text Add to dashboard Cite

Suspended clay particles inhibit autotrophic processes by reducing illumination, but they simultaneously provide surfaces for the adsorption of dissolved organic material. The aggregated organic matter can be used by heterotrophic bacteria which consequently modifies the microbial loop. Large (up to 65‐µm diam) clay‐organic matter aggregates are abundant in the water of tropical Lake Chapala, Mexico, primarily as a result of wind mixing and sediment resuspension. Because bacterial abundance and cell size each vary with available substrate, we hypothesized that the bacterial community associated with these suspended clay‐organic aggregates would be numerous and large celled as compared with those living free in the water. A persistent in‐lake turbidity gradient (from 20 to 90 NTU) was used to evaluate the relationships of particle‐aggregate abundance to bacterial cell size and planktobacterial community size. Particle aggregates are colonized by bacteria to the extent that <20% of the planktobacteria are free in the water. Bacterial biomass increased with increasing turbidity, and bacteria associated with aggregates were larger than those free in the water. Both the number of bacteria and their community biomass were significantly greater in more turbid regions of the lake than in the less turbid regions. Variation in number of particle aggregates explained variation in the number of bacteria, whereas variation in the organic matter content of the aggregate explained variation in bacterial cell size. The abundance of large clay‐organic matter‐bacterial aggregates suggests their trophic significance and provides a possible explanation for the observed discrepancy between phytoplankton production and fishery yield in the lake.

show abstract

Starvation-Survival of Heterotrophs in the Marine Environment

Cited by 244 publications

References 95 publications

Macromolecular synthesis during recovery of the marine Vibrio sp. S14 from starvation

Macromolecular synthesis during recovery of the marine Vibrio sp. S14 from starvation

Characterization and significance of β‐glucosidase activity in lake water

Association of turbidity and organic carbon with bacterial abundance and cell size in a large, turbid, tropical lake

Contact Info

Product

Resources

About