PMID- 10653721
OWN - NLM
STAT- MEDLINE
DCOM- 20000313
LR  - 20210526
IS  - 0099-2240 (Print)
IS  - 1098-5336 (Electronic)
IS  - 0099-2240 (Linking)
VI  - 66
IP  - 2
DP  - 2000 Feb
TI  - Dynamics of bacterial community composition and activity during a mesocosm diatom 
      bloom.
PG  - 578-87
AB  - Bacterial community composition, enzymatic activities, and carbon dynamics were 
      examined during diatom blooms in four 200-liter laboratory seawater mesocosms. 
      The objective was to determine whether the dramatic shifts in growth rates and 
      ectoenzyme activities, which are commonly observed during the course of 
      phytoplankton blooms and their subsequent demise, could result from shifts in 
      bacterial community composition. Nutrient enrichment of metazoan-free seawater 
      resulted in diatom blooms dominated by a Thalassiosira sp., which peaked 9 days 
      after enrichment ( approximately 24 microg of chlorophyll a liter(-1)). At this 
      time bacterial abundance abruptly decreased from 2.8 x 10(6) to 0.75 x 10(6) 
      ml(-1), and an analysis of bacterial community composition, by denaturing 
      gradient gel electrophoresis (DGGE) of PCR-amplified 16S rRNA gene fragments, 
      revealed the disappearance of three dominant phylotypes. Increased viral and 
      flagellate abundances suggested that both lysis and grazing could have played a 
      role in the observed phylotype-specific mortality. Subsequently, new phylotypes 
      appeared and bacterial production, abundance, and enzyme activities shifted from 
      being predominantly associated with the <1.0-microm size fraction towards the 
      >1.0-microm size fraction, indicating a pronounced microbial colonization of 
      particles. Sequencing of DGGE bands suggested that the observed rapid and 
      extensive colonization of particulate matter was mainly by specialized 
      alpha-Proteobacteria- and Cytophagales-related phylotypes. These 
      particle-associated bacteria had high growth rates as well as high cell-specific 
      aminopeptidase, beta-glucosidase, and lipase activities. Rate measurements as 
      well as bacterial population dynamics were almost identical among the mesocosms 
      indicating that the observed bacterial community dynamics were systematic and 
      repeatable responses to the manipulated conditions.
FAU - Riemann, L
AU  - Riemann L
AD  - Marine Biology Research Division, Scripps Institution of Oceanography, University 
      of California, San Diego, La Jolla, California 92093-0202, USA. 
      lriemann@vip.cybercity.dk
FAU - Steward, G F
AU  - Steward GF
FAU - Azam, F
AU  - Azam F
LA  - eng
SI  - GENBANK/AF191752
SI  - GENBANK/AF191753
SI  - GENBANK/AF191754
SI  - GENBANK/AF191755
SI  - GENBANK/AF191756
SI  - GENBANK/AF191757
SI  - GENBANK/AF191758
SI  - GENBANK/AF191759
SI  - GENBANK/AF191760
SI  - GENBANK/AF191761
SI  - GENBANK/AF191762
SI  - GENBANK/AF191763
SI  - GENBANK/AF191764
SI  - GENBANK/AF191765
SI  - GENBANK/AF191766
SI  - GENBANK/AF191767
PT  - Journal Article
PT  - Research Support, U.S. Gov't, Non-P.H.S.
PL  - United States
TA  - Appl Environ Microbiol
JT  - Applied and environmental microbiology
JID - 7605801
RN  - 0 (DNA, Bacterial)
RN  - 0 (Enzymes)
RN  - 0 (RNA, Ribosomal, 16S)
RN  - 1406-65-1 (Chlorophyll)
SB  - IM
EIN - Appl Environ Microbiol 2000 May;66(5):2282
MH  - Alphaproteobacteria/classification/growth & development
MH  - Bacteria/*growth & development
MH  - Bacteroidetes/classification/growth & development
MH  - Chlorophyll/metabolism
MH  - Cloning, Molecular
MH  - DNA, Bacterial/analysis/genetics
MH  - Diatoms/*physiology
MH  - Ecosystem
MH  - Electrophoresis/methods
MH  - Enzymes/metabolism
MH  - *Eutrophication
MH  - Molecular Sequence Data
MH  - Phylogeny
MH  - Polymerase Chain Reaction
MH  - RNA, Ribosomal, 16S/genetics
MH  - Seawater/*microbiology
MH  - Sequence Analysis, DNA
MH  - Water Microbiology
PMC - PMC91866
EDAT- 2000/02/02 09:00
MHDA- 2000/03/18 09:00
PMCR- 2000/02/01
CRDT- 2000/02/02 09:00
PHST- 2000/02/02 09:00 [pubmed]
PHST- 2000/03/18 09:00 [medline]
PHST- 2000/02/02 09:00 [entrez]
PHST- 2000/02/01 00:00 [pmc-release]
AID - 1044 [pii]
AID - 10.1128/AEM.66.2.578-587.2000 [doi]
PST - ppublish
SO  - Appl Environ Microbiol. 2000 Feb;66(2):578-87. doi: 
      10.1128/AEM.66.2.578-587.2000.