Biogeochemical cycling of phosphorus: Insights from oxygen isotope effects of phosphoenzymes

生物地球化学循环 化学 同位素分馏 磷酸盐 环境化学 自行车 分馏 生物化学 色谱法 有机化学 历史 考古
作者
Ruth E. Blake
出处
期刊:American Journal of Science [Yale University]
卷期号:305 (6-8): 596-620 被引量:223
标识
DOI:10.2475/ajs.305.6-8.596
摘要

Geochemical cycling of phosphorus (P) in aquatic environments is carried out almost exclusively by biota and involves reactions that are catalyzed by enzymes. Oxygen isotope effects accompanying phosphoenzymatic reactions have been determined in controlled laboratory experiments in order to elucidate processes underlying biogeochemical cycling of P, and to identify possible reaction pathways for P-compounds in nature. Phosphate oxygen isotope effects are distinct for specific enzymatic reaction mechanisms measured in microbial culture experiments and in cell-free systems. P16O4 is taken up preferentially from inorganic phosphate (Pi) in the growth medium by intact E. coli cells, producing a kinetic fractionation in the extracellular dissolved Pi pool. Inorganic pyrophosphatase is the intracellular enzyme that catalyzes the temperature-dependent equilibrium oxygen isotope fractionations between phosphates and water in biological systems, and imprints an equilibrium isotope signature on Pi that is turned over or cycled by intact cells. Alkaline phosphatase, a key enzyme involved in extracellular Pi regeneration in aquatic systems, catalyzes hydrolysis of phosphomonoesters, reactions that are accompanied by kinetic fractionations and disequilibrium (inheritance) isotope effects in released Pi. Comparison of laboratory determined enzyme-specific isotopic fractionations with those observed in microbial culture experiments and in natural aquatic systems, provide new insights into processes controlling P cycling and the relations between P availability and the cycling of N and C. Isotopic signatures associated with specific cellular processes and phosphoenzyme reaction pathways may be useful in assessing P status and for tracing P turnover.
最长约 10秒,即可获得该文献文件

科研通智能强力驱动
Strongly Powered by AbleSci AI
更新
PDF的下载单位、IP信息已删除 (2025-6-4)

科研通是完全免费的文献互助平台,具备全网最快的应助速度,最高的求助完成率。 对每一个文献求助,科研通都将尽心尽力,给求助人一个满意的交代。
实时播报
1秒前
嗯哼发布了新的文献求助10
2秒前
2秒前
小星星发布了新的文献求助10
3秒前
3秒前
寂寞的马里奥完成签到,获得积分10
3秒前
4秒前
虚幻赛凤发布了新的文献求助10
4秒前
Night完成签到,获得积分10
6秒前
huayi发布了新的文献求助10
7秒前
uuu发布了新的文献求助10
7秒前
7秒前
学术小子发布了新的文献求助10
9秒前
QJ发布了新的文献求助10
9秒前
等风归丶完成签到,获得积分20
11秒前
坚果发布了新的文献求助10
12秒前
闪电侠发布了新的文献求助10
12秒前
12秒前
充电宝应助体贴薯片采纳,获得10
13秒前
常风完成签到,获得积分20
13秒前
zhangwj226发布了新的文献求助100
14秒前
量子星尘发布了新的文献求助10
15秒前
16秒前
善学以致用应助怕黑的擎采纳,获得10
17秒前
CipherSage应助虚幻赛凤采纳,获得10
17秒前
19秒前
20秒前
txyouniverse完成签到 ,获得积分10
21秒前
闪闪寄凡发布了新的文献求助10
21秒前
希望天下0贩的0应助uuu采纳,获得10
22秒前
暴风之怒要打雷完成签到,获得积分10
23秒前
23秒前
23秒前
24秒前
24秒前
24秒前
26秒前
djdh发布了新的文献求助10
26秒前
Ming Chen发布了新的文献求助10
27秒前
29秒前
高分求助中
A new approach to the extrapolation of accelerated life test data 1000
ACSM’s Guidelines for Exercise Testing and Prescription, 12th edition 500
Picture Books with Same-sex Parented Families: Unintentional Censorship 500
Nucleophilic substitution in azasydnone-modified dinitroanisoles 500
不知道标题是什么 500
A Preliminary Study on Correlation Between Independent Components of Facial Thermal Images and Subjective Assessment of Chronic Stress 500
Phylogenetic study of the order Polydesmida (Myriapoda: Diplopoda) 370
热门求助领域 (近24小时)
化学 材料科学 医学 生物 工程类 有机化学 生物化学 物理 内科学 纳米技术 计算机科学 化学工程 复合材料 遗传学 基因 物理化学 催化作用 冶金 细胞生物学 免疫学
热门帖子
关注 科研通微信公众号,转发送积分 3971720
求助须知:如何正确求助?哪些是违规求助? 3516377
关于积分的说明 11182327
捐赠科研通 3251591
什么是DOI,文献DOI怎么找? 1795960
邀请新用户注册赠送积分活动 876171
科研通“疑难数据库(出版商)”最低求助积分说明 805340